transmission swap questions

[lscotty]

To start with I have a 77 chevy k20 that I just pulled the 350 out of and replaced it with a tbi 454 out of a 91 chevy 1 ton. I had the whole 91 chevy to work with and pulled the motor and tranny, complete wiring harness both motor side and from under the dash, all fuel lines and both gas tanks, and the radiator. I've got the motor in and ready to go now the transmission is my issue. The donor truck was a 4x2 with a 4l80e. I know you can change the 2wd 4l80e to 4wd and put a transfercase on but I'd rather not deal with the hassle or the extra cash to do so. I have on hand a th350, th400 and a 700r4 all with transfer cases and in good shape ready to go. Which would be a better option? And what needs changed to make one of them work? I know they all bolt up but dont know what issues it is going to cause switching from the electronic 4l80e to a non electronic transmission or what needs done to make it work. Any advice or input is appreciated.

[dsgb610]

Depending on the gear ratio to make a better guess but i would personally go with a 4speed tranny.; The 3 speeds eat up too much gas especially coupled with that big motor. What are your plans for the truck? And the 700 would be an easier swap i think because the 700 and 4l60 are around the same size.

[lscotty]

I believe it has 4.10 gears if I remember right. The truck is now being turned into an offroad truck. It has a rear locker now and 39" swamper irok's so gas mileage isnt that big of an issue as it wont really get good had mileage anyways.  I'm good with using the 700r4 but that brings it back to the 2nd part of the question what will that effect by not having the electronic controled 4l80e the was with the motor. Will that make it not run right? If it does cause an issue Is it just a simple pmc reprogramming to fix it? Anyone have any ideas I've searched around havent found an answer anywhere