In my opinion, you need to know which stage 6 heads you have. They made standard ports and max wedge ports. Have your heads flowed and go from there. If you have the max wedge ports, there is no reason to go to -1 heads. Any of the trick flow or EZ stuff won't get you where you want be. Once the heads are flowed you can decide which cam to buy to maximize your stage 6 program. Don't spend anymore than you have to. Also, you have to be concerned about the stock block being able to handle the increase power level without breaking. I have gone from stage 6 heads to -1's. It wasn't that much of a power gain to warrant the extra cost unless you update to the 2.25 intake valve. At that point you may overpower your block without an aluminum main upgrade. Don't forget the converter needs to match!