Need Help With Z71 4l60 to 4l80 swap

I have been doing LOTS of research and I can find any sure answers on some things. Here is what I have and if yall could tell me If I have missed anything I would sure appreciate it!

I have a 97 Z71 1500 Vortec chevy pickup with a SAS 25" lift and 44 inch tires and the 4L60e has gone out (Imagine that) my good buddy has a 4L80e out of a 94 3/4 ton pickup with a 454 that he said he would sell me for a hundred bucks and help me put in, its been sitting under a tool shed for about a year(ideas?) but I have talked to him and the guy he got it from and they said it worked fine when they took it out (the motor went bad in the truck)

First off I am wondering If this will work? The guys at nelson performance said it was definitely do-able. Here is what I know

-I have the 32 spline Input gear for the T-case (guy my buddy got the tranny from gave it to me)
-I can get the necessary wireing harness from nelson performance.
-Moving the cross member back is no big deal
-My buddy helping me has a shorter driveshaft for the back I can have
-two dealership around here said they would tune it to run the 4L80
-It has a torque converter on it.
-I have a dipstick tube and the dust cover.

Here is what Im not 100% sure about

- Is it absolutely certain that this tranny will be compatible with this truck and that the tuning is no big deal? I have seen that sometimes tuning is not necessary and I have also seen that $1000 controllers are sometimes required(is that only on carburated motors?) please let me know if you know anything about this.

- The flex plate issue has me a little confused, Can I use the one in my truck or do I need one out of a 6.0 litre truck? (the guy my buddy got the transmission from has one he will sell me on the cheap) and whats the deal with this spacer required? Im not in the know on this so if someone could let me know exactly what the word is I would really appreciate it!

- Also I don't have access to a lift and since the truck is so high up (40" from the ground to the bottom pan of the transmission) I know a floor transmission jack wont reach and that a stand up transmission jack is to tall. Any ideas? Thanks!

BUMP. I would really appreciatte any input. Thanks!

I think you have the 0411 computer? It should be no big deal for nelson to tune your computer to work. Someone correct me if I'm wrong

Im sure nelson can handle the tune, also to get it down to working level just take the tires off and bring it down til the hubs are almost to the ground then you can use a trans jack.

I did the math and even if i put some 28" tires on the thing it would still be too high for a trans jack, any other ideas? are there any mid level trans jacks out there? also where would I be able to rent one?

I think he meant leave the wheels and tires off completely. You can set some blocks under the axle tubes or something

Yes that's what I meant.

I did some measurements and I dont think that will work, it would be close though, I havent looked at a ton but the floor trans jacks I have seen only reach 26to 28" and It would still be higher than that. Any idea on where I could rent one though? Im not even sure where to get one without buyin one.

build a tall wood box with a ramp to put the trans jack on and make up the difference on the limitations of the jacking height. Once you have it out and down you can just roll it down the ramp towards the rear end. I've had to use a come-along across the frame rails and under the trans to jack one up to my 92 truck, once. It was tricky but got the job done.

yea I have thought about building a ramp or something, that would probably work it just seems like there has to be something easier lol. I think between setting the truck on the ground and building a small ramp would probably work. I just wish there was something a little easier. Any other ideas welcome!

BTW that come along idea is great, thats the kinda stuff im lookin for!