[Mike C]

So it doesn't bolt right in. Neither does a gear set or a differential set itself up.

I have 3/4 ton axles from an '86 in my '72. I removed and reused the donors spring perches. I used the OEM shock mounts from my original axle. No biggee. And even if you had to pay to have that done, no more than a couple $100.

I paid $300 for the Suburban with a broken motor. I bought another '83 3/4 ton sub for $200 and a '76 Blazer for $300. They are out there, and they are cheap. If you can't do this swap for $1000 you didn't try. 1/2 ton axles are out there it seems all over because 3/4 ton such a better choice IMO but if driveability is the goal, the 1/2 tons will work great.

If you have the whole thing apart anyway, you could also swap the gear set into the existing 12 bolt housing (assuming you get a '73-'79 donor and not an 8.5" 10 bolt truck). Either way, the truck will be much more driveable and safer with discs.