there is a ton involved with it.
what tranny you want to use?
you can use all the 4.3 accessories (alt, power steering, ect)
you will need a bigger radiator
adapters to t-case or tranny, depending on what you use.
aftermarket wire harness, or strip down an existing harness.
custom motor mounts, crossmember.
fuel pump, if you dont have one already.
uumm, i am sure there is lots more.
i am gathering the parts right now for my swap.
have the 4.3, sm420, toy tcase adapter.
still nedd lots of parts though.
derek