Yeah I agree, and you can use an LS1 or LS6 intake on the LS4's, but still require a little modification to make them sit flat but it's easy and no big deal to get done. They flow quite a bit better so it's an easy power adder.

After researching I want to do this more and more haha. I'm just not sure if I should go the LS4 route (and have to deal with the starter stuff) or use the GM truck 5.3 V8 and just have an adapter made for the tranny.