There are "low head" allen cap screws. I prefer those to the button head for the cam button application. Also, make sure you check and adjust the cam endplay - I've yet to see one of those buttons fit any cover without something needing adjusting. If its too tight then a solution is Proformance cover gaskets. If its too loose you can cut a feeler gauge and use a piece behind the button to space it out. Contrary to what you may have heard, on a roller bearing button you do not need any endplay.