Motor mounts, motor mounts, motor mounts
seems like the first thing we need to do is find a way to install the actual engine in the truck... and for that we need to find a way to bolt it in some how, and there is an obvious difference in the blocks motor mount system SBC (3 bolt) vs LSes (4 bolt)
many choices, people seem to like the aluminum LSX Innovations (some hate them cause supposedly they crack, but I hear that is user error, see one of the videos below)
I like making my own solutions, so I really dig this young man and how he is a problem solver, rare these days in the iPhone iGeneration
MrJohn613
Budget LS Swap : Adapt Motor Mounts Free DIY question is, would you do this?
Bad Luck Garage
WHICH LS SWAP ENGINE MOUNTS DO I USE? recommends the LSX Innovations motor mount adapter plates
these work if you want to keep the factory LS AC according to Lonnie's Garage (Puppetkicker)
1984 C10 Project ---- LS Swap Part 1 (Motor, Mount Adaptor Plates, and More)