First off thanks for the input.
XcYZ - Yes I seriously want to put a Duramax in a Camaro and not just for the wow factor. The Duramax will put down loads of torque and I believe that I have seen a few in the diesel truck forums getting right near 600hp with no work on the internals of the engine. Now while that is not a huge amount of horsepower it would be a really dependable powerplant that also gets great mileage vs gas engines with similar power.
Ketzer - Thanks for info. Yeah I don't like doing much by the book either and most the car guys I hang around with here all think I am crazy also. I am planning on keeping things fairly simple as far as the engine goes. My main concern is dependability and driveability as I do plan on driving this car quite a bit once it is done. I am thinking about just getting a low mileage engine and trying to use the factory wiring and computer. Then just doing some of the upgrades to it that are available to the truck guys. I still need to do some research on the truck boards and see what product will be the best way to reach my goal. I am planning on aiming somewhere between 500 and 600 horsepower but if I get a little more I won't be upset.

But hopefully that will keep engine cost to a minimum.
CraigMorrison - is there anywhere I can find some info on the 57 Caddy that was mentioned? I have not seen that one yet.
Thanks Again Everyone