Well believe it or not, at least on my carbs, the 10-32 screws threaded right into the existing threads. If you have a 10-32 die , see if the stock screws will thread into it. Since I've installed stainless screws, never had a problem with them seizing in the cover, like the stock ones are prone to doing. But even at $2 each, if you bugger up the covers trying to get a rusted screw out, I think the covers would be alot more expensive than $8! If you do get a screw stuck in the cover, before you ream out the screw head, get some valve grinding compound, put some on the screw head and then procede with a screwdriver bit in a 1/4 inch socket on a ratchet. Don't try to remove it with a normal screw driver.