search down....auto to manual tranny swap????

[speesh]

I have to change my old junky 3 speed for an automatic in my 71 half ton suburban..... here is what I think I know about the job.
1. I need a flywheel, starter, torque converter, shifter, and crossmember, is there anything else?
2. I am taking out a three on the tree tranny, I think I can put in a turbo 350 without changing the driveshaft.....
3. I just happen to have a parts truck with a rebuilt tranny.... but its a turbo 400! and a 3/4 ton, while my burb is a 1/2 ton.


Question.... if I use the 400, can I use the driveshaft from the parts truck? It is a 69 longbed. Or would it be easier to try to get a turbo 350? Then I wouldn't have to do all the work of removing the other tranny from the parts truck, but I would have to get all the parts.

Need IIIIIINNNNNPPPPUUUUTTTT!!!!!
I know this has been talked about on here many times, but search is not working so I have to ask. Anyone? Anyone? Bueller???
p.s. here is a picture of my burb overlooking Panamint Valley, this is aout 45 minutes from my house...