There was a recent mag story on converting the 4thgen rear to 3rdgen use, covered the whole build start to finish, from pulling the tubes to cutting custom axles and stuffing a new posi, then weld and straighten housing and re-assemble.

Thought it was GMHTP, but it wasn't in any of the issues I have, it was very recent.

Any leads appreciated!!

 

you dont have to cut it at all just bolt it in

 

IIRC, the 4thgen rear axle is 4" wider, would need new wheels, etc. This made it identical, flange to flange, just a lot stronger in the gut.

 

Bolts right into place. Just need 4th gen wheels othewise your tires will be sticking a little further out.

 

BUT - 4th gen wheels up front mean spacers to clear! The 4th gen rear fits in the third gen, but like was said, the stock wheels stick out about 1 3/8 inches farther on each side. With new springs and shocks, doesn't create any rubbing issues - I have Eibach Pro Kit on mine with Bilsteins and I don't rub anywhere. But some don't like the look. Me - I can live with it for the LS1 rear brakes and posi - and the rear only cost me $150 complete.