Mine does about the same thing, Ultima states when you put the end cover on pry up on it when you tighten it down. I noticed too when you pull the gear out onto the ring gear it may not snap back in, if you roll your belt a tad bit, the gear immediately returns back in. Mine too covers about 3/4 or a little more. I tell you this fix is the only way to go. When I first installed my belt drive and starter i swear 90% of the time it would grind! makes you wonder how they even sell it as operational functioning product. The Jack shaft fix completely fixed it, has yet to grind once. on another note: I did however have to drill out the inside of the cover deeper, at first install the jackshaft would not throw all the way out and the gear was only engaging only about half the ring gear.