need help with a 2wd 79 to 4wd 78 cab swap

[$pit]

Project: im planning to swap everything off of my 79 2wd SWB (body,engine,etc) to a 78 or 74 4x4 SWB chassis.
Questions:
1. the seller of the chassis doesnt know if its a 78 or 74. does it matter?
2. my 2wd is a manual and the 4x4 is auto, will it be easy enough to keep the manual?
3. were there any significant changes in the frame, body mounts, etc from 74 through 79?

Im deployed right now and only have a number from the seller. so i cant email him right at this moment, but hes only selling the 4x4 for 800 bucks
any information would be very helpful.
thanks matt

[74 stepside]

All the body mounts should be the same. Only difference might be the transmission hump. I debating on doing the same thing because I can get a 4wd chassis for $650.

[$pit]

yea ive been reading alot about it and i just want to be sure. i love what i have in my 2wd just wish i would have started with a 4wd lol.
thanks