The lt1 engine responds very well to mods, decent aftermarket for it as well. i have a few laying around an contemplating doing it myself. Main problem i see is i would like to keep the stock lt1 fuel injection system and i would have to run the lt1 computer. The problem with that is the optispark if some arnt familiar with that it is the front mount cam driven distributor. They are very temperamental and wouldn't like the mud or water. I do believe u can run the 4l80e with it if u planned to run the stock lt1 fuel injection system u would have to have a mail order tune for that trans tho as the lt1s use the 4l60e. You could do it a easier way and pick up a lt1 4bbl intake and get a tb adapter and run the stock tbi tb or aftermarket one, and use a regular distributor. The lt1 block isnt much diff from ur SBC it just uses reverse cooling (no water flow through the intake) aluminum heads with smaller chambers 10-4-1 compression hyperutectic flat top pistons, gm's "pink" rods and s steel crank, the water pump is cam driven it uses a gear that goes to the timing chain which most convert to a electric water pump. I have a few built lt1s as u can see in my sig, one is a forged 383, one is a cam only, one had a Heads cam an intake package an full bolt ons, then one just has minor bolt ons. There very strong engines make great power an torque monsters down low in a fbody. hope this helps btw im new to the forum so bare with me.