As I am running adjustable cam gears, I thought it would be a good idea to make a removable cover so that the cam timing can be adjusted without having to remove the whole cover, To do this, I first cut a hole in the cover just large enough to enable access to the adjusting bolts on the cam gear, then cut a piece of sheet aluminium to cover the hole and then drilled holes for the M6 bolts, using helicoil insets to form a good thread in the original cover.