Powermaster Starter required Milling to Install

Replaced an OEM SBC starter motor with a Powermaster starter. The installation reauires adjustment to the gear spacing which usually requires shimming when the spacing is too tight. In this case the gap was too large. Milling of the starter mounting block was required to obtain the proper tooth spacing. Powermaster tech support was great and extremely responsive. The SBC block is 3970010 1969-1980.