Mismatched parts???

Well, I searched the internet and found some pics of the alternator brackets for AC equipped big blocks. Lo and behold I have all of the brackets (not sure if I have the spacers yet, though). BUT, I've got a huge (1/4" or slightly larger) air gap between the adjuster arm and the alternator AND the bolt hole doesn't quite line up to the slot...Which part is wrong?

I just looked at my BB and it looks identical..as far as the upper bracket...except my lower bracket is right up against the ALT, is your lower bracket bent? or not the right one?

Looks like you have the alternator on the wrong side of the top bracket?
I've had pulleys not line up before.

Yep,bracket goes on front !

Having just back fitted AC to a 6 pack motor for a friend....is your idle pulley lining up with the water pump and outer crank pulley? Angle of picture is deceiving. The reason I ask, the small cast 2 hole spacer also comes in different lengths depending on year. Additionally the 4 crank pulley come in slightly different size beside the asymmetric/ uniform hole pattern. 68ish? and down used a 5/8" PS belt, while 69ish? up used the 1/4" belt, which pushed the outer pulley out further. Hence the different spacer piece.

Not on this setup and that would make the air gap worse anyway.

Idler and WP and Crank pulleys line up. It doesn't really look like it, but they do.

The spacer is irrelevant to the alternator problem, but still could be the wrong bracket. It is likely the bracket that came off that engine when it was in the '76 truck, but the engine is a '69. I can't tell you where all of the parts came from, but every thing looks the same as this kit.

https://dantesparts.com/i-30499102-...440-big-block-with-air-conditioning.html

From Bouchillon's page.

Looks like my 67 383 is way different.

That kit looks like the 1971 and above air conditioning mounts and brackets

It's the '68-70 kit, I believe. At least part of it is. The idler is too far out upon further inspection so I believe it is for the early setup which has no brackets behind the standoff. That would account for the alignment issue. That doesn't explain the alternator bracket problem. I have a little more than 3-13/16 from the head to the fixed bracket. This bracket was bent when I pulled it out of the pile, but it was clearly not a factory bend.

Ok, '69-70, but I was close...

Does the alternator align properly with the AC and Crank inner 2 pullies as it sits? Straight, not at an angle? If so either that mounting bracket that is slotted is not correct, and there may be variations on it too. Or something is bent as you said. I can check tomorrow if there were 2 variations on that bracket. You can make anything work with some spacers as long as pulley alignment is right.

Pulled out to the slotted bracket the alternator pulleys appear to line up to the crank pulley. I don't have the AC brackets so I can't look at that yet. I put a little tweak on the upper alt bracket and it looks like it will work.

I did some research and it appears that the idler bracket is early and this is the later setup. Not sure what changed, but I changed the spacer behind the pulley (between the pulley and bracket) and got it to align with the WP pulley. So progress today. Might prime the oil this weekend and perhaps fire it up in a few days. Gotta pick up a few things first. I'll run it off the battery to start with.