I am pretty sure the first year of the 4L80 (91?) was non electronic. The company I worked for at the time had 4 or 5 G30's with first year 4L80's and all of them went through transmissions like crazy. Took GM a couple of years and electronic control to make them durable.
One of the biggest reasons I advised you to get a heavier truck was because the swap to a 4L80E will not be cheap.
I would suggest looking for a salvaged Vortec 350/4L80E/NP241 combo (or whole truck) to swap into your truck. If you were to get the whole truck, you would have 3/4 to rear springs and a 14 bolt rear (semi float, good enough). I would still advise no lift for better handling and less wind/road resistance, but 4" lift and 33's wouldn't be too bad.
The Vortec would be good power for what you want to do and having a whole truck would get all of the parts needed. I have seen wrecked 97-99 2500 trucks go for $800-1000.00 around here (I4x4 from this board bought a whole truck for the Vortec/NV4500/NP241 w/125,000 miles and frontend damage for $800.00). /forums/images/graemlins/thumb.gif
