Not yet, It was getting late and I was beat. In looking at the 2nd PP and 4th pic (flywheel side of disc) one can see the same circular ring (pattern) in the middle of both. It's there on the FW as well but not as prominent.
The pattern being more visible in the PP and FW side of the disc makes me suspect one of them wasn't flat.
The ring is also visible on the flywheel but one has to really look closely for it to show.

I have to now establish why the z bar is not straight and level which I suspect may be the Bell housing pivot mount. Will likely have to wait until the trans is back in for that adventure. Wish I had a stock pivot mount to compare it to as well as a stock z bar.
thanks to all again and any input is appreciated.

Jack engine up to stock height then fix Z bar, whole lot easier without that trans in the way.

I certainly wished I had thought of taking some measurements before pulling the trans
I have a new pivot mount coming from Brewer's. I'll compare it to what's in there now and go from there. Might slip just the BH, trans back and crossmember back in to do so

It looks dry in there, at least best I can tell. But it sure sounds like how a contaminated disc behaves. Anything coming from above, like from the oil sender area?

Maybe somebody could give you dimensions from a correct z bar and weld up something from the pile?

Nothing wrong with a diaphragm clutch, other than installer error and lack of driving skill. I won’t use anything but a diaphragm and centerforce has always worked well for me. You checked off the big no no, the over center spring. So it had that in there for both clutches. Plus a linkage mess, plus the slick flywheel, plus we don’t know how any of those involved broke it in. I think at this point I’d solve the linkage issues and go with all new parts and do as much break in as you can yourself. With the spring out of the dash it should end this ordeal.

If FW isn't flat, could be saved with a very light machine over, save some $$.
PP could probably be reused, unless very contaminated.
Easy for some to say "buy all new"
Z-bar alignment isn't that "super" critical, as it will shift as rubber mounts "settle" from new.
Doubt it has any effect on clutch chatter.
But will with pedal operation: i.e. smoothness etc.
But still nice to know you are using the correct one.
Best to you.

.........please show the DIAL INDICATOR readings for the alignment of the bell house to crank center-line and squareness to the crank/b-h centerline......

This is a fundamental [basic] check that is required and nothing can be resolved without this check and correction.

Crank needs the roller pilot bearing!

Wrong type of clutch, bad choice in disk material.
Is that a crack in the flywheel?
Is the flywheel thin from too much machining?

Something is just plain wonky here. I don't have the experience with a lot of clutches like some members have but I've never see a pressure plate like that. The thin ring that appears to be overheated to the point of bluing the PP would really concern me as that appears to be the only significant contact area.

There are only a few things that cause chattering. Grease or oil on the flywheel, pressure plate, or disc. Or the friction material of the disc. Street type disc's don't usually chatter. More toward a race type disc does tend to chatter a bit. If the flywheel was not resurfaced or not resurfaced properly, it should not chatter, but the clutch will slip.

I believe it was for a stock using their headers , I grabbed it to gain some extra clearance with my 2.5 mandrel bent headpipes and for potentially putting headers in when the stock appearing bug stopped biting me . Haven't finished it yet .

I wouldn't use a roller pilot bearing , the input shaft was not hardened originally for a roller bearing .

What bad happens with a roller pilot? I never had trouble and beat on my car as much or more than the next guy.

I would think it's going to wear a groove in the shaft over time. Some people say we don't drive the cars enough to worry about it but I'm not one of them.

YMMV

Responding to all,
Dry as a bone inside the BH and the car hasn't even left a drop of anything on the floor. Even the inside of the inspection cover was dry.
I don't think the linkage being out of whack caused the issue BUT -------
The flywheel and disc appear to be flat in checking them with a Starrett straight edge and light behind. If anything the PP appears to be a bit concave across it's surface. There are also marks on the inside of the diaphragm fingers where it hit the retainers for the clutch springs. This I assume was from over adjusting the clutch at some point. (See pic below) It was still grabbing 2-3" off the floor when it came in and i will guess had at least an inch of preload on it.
The pattern on the PP is strange in that it appears to have been grabbing in the center and more so in two areas ~ 150 degrees apart. The same "ring" is evident on both sides of the disc but more so on the Flywheel side
The only thing I can conclude at this point is either the disc or PP was out of whack, or there was some kind of contamination involved. Maybe Bubba had a greasy lunch
I have ordered a NEW CF clutch assembly and flywheel as well as linkage parts from Brewer's. not sure or anything other than the Pattern to me indicates there was more contact in the "RING" on the PP and I am tempted to suspect that as the cause DUNNO. I may run the pictures by a tech at CF and see what his thoughts are. I will keep posting updates.
thanks a bunch for all the help/ suggestions

1, Get a new pressure plate, clean it very well with blue shop towels and brake clean and do not touch it on the friction side afterwards, even normal skin oil is bad.
2. Get the flywheel re-ground by a different shop, they used too fine of a stone, that is not an 80 or 90 grit finish and it has weird patterns off to the right like someone hit it with a cookie disc or something. Also clean it with blue shop towels and brake clean and do not touch it afterwards.
3. get a new friction disc and do not touch it
4, make sure there is no excessive grease on the input shaft or throwout bearing (or anything in there for that matter as even a little tiny bit on the friction surface can cause issues)

Do not let it get any greasy hand prints on any of the friction surfaces of the disc, pressure plate or flywheel!

Doing all that will cure any issue inside the bellhousing.

Do the clutch disc springs show any contact to match the pattern on the PP fingers?

Those marks look like the clutch is being depressed to far ???

The diaphragm fingers aren't that strong and will keep going once the clutch is released ... think speed shifting when going down the track, you are slamming the clutch pedal as fast as possible...

That is why you set plate departure and not freeplay as the FSM suggests. THough in this case the OP's freeplay is good.

All good points but I’ll add, do not grease the pilot busing, it’s silicon-bronze it lubricates itself and will not cut grooves like the roller bearing will.

Replies to all:
Hotrod Dave: Don't know if you read the entire post but the car has been through two shops and two New clutches with ONE resurface that I am aware of. keep in mind the car is 55 years old so who knows how many over the years. It is getting all NEW components from Centerforce including the flywheel

6pak: No, but the metal tabs that retain the springs do
John RR: The fingers were definitely hitting the spring retainers on the PP side of the disc. The car when it came in, had 1/2" + of preload on the fingers with the clutch fully engaged (pedal released) I strongly suspect they likely adjusted the linkage (too long) trying to alleviate the chattering during their troubleshooting process, And that is likely where the marks came from. (BUBBA says OOOPS 😲🤫, that's a bit too much, git me another beer and back that off of a bit) 🙄
Sniper Initially the departure was somewhere beyond .125". Could've likely driven a greyhound bus through the clearance ( OK joking a bit).
Cudaman I use a high temp brake grease from bendix that does not melt nor contaminate friction material. I have a 12 oz tub of it that was given to me by a couple of reps from bendix quite a few years ago. The product has been discontinued (upgraded?). They at the time specifically mentioned pilot bushings as another application for the product. Having turned some pilot bushings in a lathe older ones seem to produce a noticeable amount of oil while newer ones produce much less. Same cutter, RPM, depth of cut etc. So, not knowing if it's a better lubricant, cost cutting or overseas MFG. I use a light coat inside the bushing and a very light film on the input shaft. haven't had an issue yet
Will keep all posted,
thanks

Seriously ungood, probably most of the issue there. That's allowing the pedal/linkage/throwout bearing to over travel, which is why the fingers are hitting.

I would also balance the new flywheel to the new pressure plate.