After reading a bunch of threads on suggested fixes for the dreaded hot start issue, today I installed a Summit mini-starter (product 829000) in my bbc auto 68. All the clearances were good and did not require any shims. After getting it put back together, when I turn the key, all I get is a single strong click which I am assuming is the pinion hitting the flywheel and that is it. Battery reading between the posts is 12.48 and it was starting fine (when cold) as of two days ago.

When I checked the clearances on the old starter, I could pry out the pinion and it would mesh with the flywheel no problem. On this one, most of the time when I pried the pinion out it would not line up with the flywheel teeth and required me to manually rotate the pinion to get it to engage the flywheel. And honestly, I don't know how many teeth the flywheel has but it seems to line up if I rotate the pinion?

1) Any suggestions on what the problem might be?
2) When working properly, I assume that the pinion turns as it is first engaging the flywheel such that the little angle cuts on the pinion teeth align with the flywheel teeth?

Thanks in advance!!