I know there was a post where the whole gear carrier
from a later truck would fit into rear housing
of an earlier truck making the process easier.
Though I don't remember the thread at the moment.
However to do all those things you pointed out
I'd rather stay with the stock gears.
My son does not need or want to do 70 - 75 MPH
and he is not looking to raise MPG.
I did this with my fire engine that has an Eaton rear. I found a newer 2-speed pumpkin that bolted in and swapped out the single speed, it gave me 6.14/8.36:1 ratio which was better than the stock 7.17:1.
I don't think there is any help like that for the GM rears...
Mike B
