Frame tweaked and rear shackles?
 

Just got my 6 inch lift finished up yesterday, and after getting an alignment, the tech said my frame looked pretty tweaked. Said I'd probably have to get it straightened out by a shop - if anyone's ever had that done, about how much am I looking at? What about the frame strength/integrity after straightening? I'll have to call around tomorrow for some quotes I guess.

Also, more importantly - has anyone found a source for stock/replacement rear shackles for a 70 blazer? I can't seem to find anyone who makes them, and they're not exactly abundant in the junkyards here. I'm also not quite ready to go for a shackle flip just yet (plenty of other more pressing things to fix first). I was thinking maybe some short front shackles might work? I was gonna call the dealership tomorrow, but guessing that's going to be a dead end...

If the "tech" said the frame was bent, how was he able to give it a proper alignment?

A properly repaired frame is strong/stronger than new. It depends on who is doing the straightening.

Take some measurements to check for square....find out for sure.

Well, my measuring isn't exactly foolproof, but I can't seem to find any glaring problems underneath. All the body/motor/transmission mounts seem to line up just fine, width is good, and several diagonals match up as well.

The problem is, even when sitting flat, the left side of the truck is about 1 inch lower than the right (springs and shocks are brand new). The front axle is also shifted about 1 inch to the left. All the mounts look straight, and it tracks and brakes fine too. Guess I'll keep looking, hehe.

i just put a lift on mine and also replaced the bushings. i had the frame jacked up in order to replace the bushings. i then tightened the shackle bolts while the frame was still jacked up. this caused a difference in hieght because the shackles, when tightened, will hold the frame up higher if they are not set right. i talked to the local garage and the guy told me to loosen the shackle bolts and then have all the weight of the vehicle on them, then tighten.

this worked for me, you might try it.