Well, if you plan to put a small supercharger on, I suggest you dump the 305 heads, buy a set of aluminum heads and aim for 8.5:1 compression so you can run on pump gas but is still high enough to make good torque for driving on the street. The 750 you have on there now is too much carb for the motor, but with the supercharger installed it may be perfect, if it works with a supercharger. Despite having forged pistons, you probably have a cast crank so you will need to be mindful of the boost. I would recommend staying around 400 hp and nothing more. You'll want a cam with a wider LSA, 110 to 112 degrees should do you well. .480 valve lift is on the upper end of what you need with a supercharger to make 400 hp.