A body with an A833 and a Gear Vendor installed

Changing a B/E body trans to an A-body involves changing the tail, the Mainshaft, and usually the rear bearing.
Additionally, the B-body front retainer will not fit into the standard A-body BH. This is an easy fix by using the A/F-body overdrive BH and front retainer. Some guys have machined the 4.35 BH to fit the B-body retainer. (IIRC 4.80)
You could even use the entire alloy overdrive box/retainer/and tail but you would need an A-body M/S and 3-4 synchronizer assy.


For my 367 small-block, I stuffed the guts of my standard A833, into the alloy-overdrive box, even using the overdrive M/S and 3-4 synchro hub, by fabricating a bushing for third gear, but I wouldn't recommend it for too much more power/torque than what my engine makes.
I don't recall the weight savings going from all-iron to all alloy. But I can tell you, that at age 45, I was still throwing that all alloy box up there by myself. In fact, it almost floated up there on it it's own, lol.
If you need a HD alloy box, I got mine from Passon.