So, your opinions on shortening a 8 3/4" without a store bought jig. I've seen many videos where guys are using 3" channel and large c-clamps to clamp the housing together and to hold it "straight" when welding it back together.

Short video as an example https://www.youtube.com/watch?v=Jql_IVp_RF0

Backyard butchery or darn close enough consider factory tolerances and 50 years of hard use???

I've see people use a large tubing cutter to cut the housing. Makes straight consistent cuts. Then beveling of the ends and clamping it secure and straight just like in the video you posted. I had a shop narrow my 8.75- had them do everything.- new ends and a drain plug welded into the housing. New tubing ends and new green bearing installed. The shop used Moser to cut and respline the axles. It was not cheap. Total came to $700.

Did my first narrowing in the late 80's without a jig. Still going fine. Raced for years and street driven. Tires wear fine car tracks straight. I've done plenty since but using jigs. The touble is with the housingings themselves. They're not all straight. So if you just line the ends up on the tubes the centerline may not be true. That being said, it won't be any worse than when you cut it apart. The last one I did the housing had to be heated and quenched several times to get it straight enought to line the one end up properly.
Doug

Chrysler never made a straight rear housing , i gust narrowed a dana 60, a friend let me barrow a narrowing tool from him, that way it is nice and straight, nice job

And the outside of the housing is less straight than the inside.

Oh man, that's a huge offset! I always thought they may be out some, but that is significant. Good to know.

I am not fond of modern steel. I can't tell you how many pieces I have bought bent from the day it was made.

Here is another method with angle iron. Not an axle but a similar technique could be used.

I had no idea how bad they were out of alignment until I saw that picture John posted above. Wow.

Made my own. Only used it once. Looking for excuses to use it again. LOL!

I love doing as much as I can on my car. I built the engine, transmission and suspension.

When it came to the Dana 60, I wanted it done right. I took it to a local race shop that had all the tools (that I didn't) and years of experience (that I didn't) and they charged me a nominal fee to narrow it, weld on the ends and put in a different gearset.

All in with new axles, bearings, spool and the cost to cut down a full floater, I'm in it for around $900.

We did set the pinion angle in the car and burned in the pads at my neighbors house who is really good at welding and has all the tools (that I didn't).

"Sometimes a man has got to know his limitations." - Clint Eastwood

Nice work!

Johns looked like the last one I heated and shrunk back to being close before welding.
Doug

Years ago I had a cottage industry shortening housings and shortening/re-splineing axles. IMHO the only correct way to shorten a housing is with a bar all the way through both sides of the housing.

Even with the bar installed, after the welds cooled, the bar wouldn't easily turn so I would have to heat and shrink the housing into alignment. Admittedly, I'm not the best welder but lots of experience showed me that ANY welding on a housing will result in warping it.

I used a 1.25" ground SS bar fore my setup

Being your unit is bolted to a fixture, does you bar come out without much flogging?

I used to work in a shop that did a lot of rear shortening and/or straightening. They had the Mittler Brothers setup which is the spacers and bar. 8.8 Fords were the worst for being crap from the factory.

That is the reason for the modified open carrier you see in the attached pic, I can remove/loosen the caps if needed to make everything more moveable if I get any excessive distortion after welding.
Not sure if my pic shows this, one shaft "bookend" is bolted solid, and the other is placed/clamped as needed on a ground guide plate mounted to the robust I beam base.

I have heated and shrunk sheet metal but an axle tube i have never done.

What is the process to heat shrink an axle housing to pull it back into place?

Figure out which direction you need to pull it, heat a portion of that side of the tube cherry red and hit it with a water-soaked shop rag. Let cool, repeat as necessary.

https://www.youtube.com/watch?v=z76i3MWi_r8