Pinion angle, 14 bolt swap, 4" lift spring

[stangtjk]

I'm working on the rear suspension of my 72 to fix what the previous a$$clown put together.

So someone prior to me swapped in a 14 bolt and did a terrible job with it. Not sure what the 14 bolt came from but the spring perches were about 1" too far outboard and whoever installed it just forced the springs out to match. This was on top of a 4" lift block that had two slivers of flat bar stock welded on the rear of the block to presumably to adjust the pinon angle. I use the term welded loosely as there was only a few tacks which didn't stick to the cast blocks as they fell off when I unbolted everything.

The shock mounts they had installed were some goofy aftermarket ones that had 4 holes for positioning the shocks but the same quality of welding was involved. Two of them I knocked off with no grinding in about 6 hammer strikes. To top it off they weren't located in the right spot either. They were also about 1" too far outboard so they used a longer bolt through the 2 tabs and instead of the shock being between them is was cantilevered off to the inside. Both mounts were all bent up as a result.

So yesterday I cut off the factory spring perches, crappy shock mounts and tossed the lift blocks they pulled the hack job on.

Now I've got everything mocked up with new spring perches and 4" lift springs and need to figure out where to set the pinion angle. The lift springs came with wedges attached but I think I want to toss them and just set the angle with the perches. I know the angle at the diff should match the angle at the t-case but right now all I've got are axles under a bare frame. Anyone know what angle I should be shooting for?