I need some schooling on my new A833!!!

Yes as SCCAChallenger pointed out all the race trans were 18 spline input. They were developed for various applications from Pro Stock Hemi, Pro Stock small block, Trans AM competition, and NASCAR. Some were more available than others, I ran the Red and White stripes, and I never saw some of those listed, though I was only interested in drag applications.

I don't think the average modern day enthusiast would notice much difference from application to the next for some of the gear differences, but these were felt to be important at the time to those trying to set records when people relied on these factory based trans.

A more important question I would offer, what is the intended use and is the trans slick shifted? Does it have synchros? As usually the drag trans did not use them.