UGH!!! Starter Issue. HELP!

I have yet to use any of the mini starters. I'm not aware of any "fit" issues, other than the usual--something bent, broken, or dirt, debri, etc

Sounds to me like something wrong in the starter

If the solenoid is pulling the gear (drive) out or if the gear drive itself is AFU. The "gear drive" (sometimes called a Bendix) has an over-run clutch/ ratchet so the engine does not wind up the starter motor when the engine starts.