I have a Mercruiser 120 hp 4 cyl. 1983. I am installing an Arco starter and they sent me a shim that is 1/16" thick. I installed the starter without the shim to measure it. The starter grinds and it has full contact in the teeth. Will this shim be too thick? How much will it back the teeth out? I do not have the old starter or the shims. Thanks in advance as always.