When energized, the starter's pinion gear bangs into the side of the flexplate, with a ringing sound, instead of engaging it's ring gear teeth. Specs: Engine: '58 354 Chrysler truck Hemi. 8-bolt crank flange. Trans: 1992 Chevy 700R4. Adapter & flexplate: Black Mountain Hemi, since gone out of business. Starter: Standard Mopar 2-bolt starter. Checked good at local AutoZone this morning. Here's a 3/16" allen wrench between the ring gear teeth & starter shaft. As an experiment, I inserted a 0.075" thick flat washer on each starter mounting stud, between the adapter & starter housing. This moved the starter forward, *away* from the flexplate. When energized, the pinion just barely engage the ring gear (<25%) but did spin it. It didn't slide back & disengage when de-energized. Shouldn't it have? Finally, I removed the washers and left the nuts on the studs, loosely holding the starter in place. I bumped it over- the starter wobbled around, then the pinion fully engaged the ring gear and spun the motor. This tells me that there is *some* starter orientation that allows the gears to mesh correctly. BTW, it still didn't disengage when de-energized. At this point, what would you do? Anyone ever shimmed a Mopar starter (like a Chevy)? Am trying to post videos of the 3 scenarios above, but the MP4 format isn't being accepted.