Everybody makes parts, harnesses, etc for ls swaps, and there's more research and info available. If I was looking to do a swap, there's only one option. If wanting something more bolt in then a stroker. But you can get the same power, more reliability, and lighter package out of a basically stock ls than you can a built 4.0.
Well, multiple options (4.8, 5.3, LS1, LS2...)