Send it to Whipple. He can put a stage 1 program in and you'll get a little more power than a stock HO. No one else can do it.

Besides cam, ecu and supercharger kits you could also start with a simple flame arrestor upgrade and even a exhaust system upgrade to increase power. Hardin Marine makes a nice 496 billet flame arrestor with increased surface area and Lightning as well as Hardin makes a great header system for those motors. Like everyone has mentioned it really depends on how much you want to spend on the project.

Just like to say thanks again for all the help Jeff