NV3500 to T56 swap?

[24 Karat Brown]

I recently found a guy on instagram who swapped a LT T56 into his truck while keeping the original 350. My truck is a 94 TBI 350 with the NV3500. Does anybody have a write up on the process? My NV3500 is good, but its obviously not built to be abused if you couldnt tell by the "what gear is this?" style shifting. I plan to keep my 350, its as strong as can be for 201k miles, she was taken care of. I always felt I could use another gear for highway use. She runs about 2200-2500 around 65-70mph. I beleive I was told I had 3.83 gears, but I dont know how to be sure. If anyone has done this swap and has a writeup/parts list please do tell

 

[df2x4]

This is on going from a 60E to a T56, but a lot of the info should still be relevant.

http://www.gmtruckcentral.com/articles/t56.html

 

[bamabound]

Gears are probably 3.73. If it's still legible, there will be a decal in the bottom of the glove box with the RPO list. GT4 will be 3.73 and G80 for limited slip.