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LOSA6240 5-40 x 1/2” Caphead Screws (10)........................... $2.50
The eight screws that come with the one piece mount are all the same size. The four that bolt the engine to the upper mounts should have a small #4washer on them. I like to use loctite on the screws bolting the engine to the upper mounts, but not the bottom screws mounting the upper mounts to the lower mount. I do regular clutch maintenance at the track so they don't get a chance to loosen up.