A833 questions

Hi, I'm installing an A833 in my '63 Dart, I was going to just install it, but started looking at it a little closer. Actually started with installing o-rings and see I have to remove the reverse, detent? A few youtube videos and I can do this! I have overhauled a T90 Jeep transmission with the help of videos, this looks easier.

However, immediately ran into removing the retainer in the front, and the part won't slide off, looks like the gears are mushed somewhat but don't understand why it would be that way. See pics below please.
I know no history of this transmission other than a Mopar guy had it close to home. Actually he had several A833's of different models.

A833 overhaule.jpg

A833 overhauld.jpg

There's little slop in the front bearing and little in the rear, but thought I'd go ahead and replace them anyway.
A833 overhaulc.jpg

This is what caught my eye first, a chip in the this gear, but no others. so, take the thing apart I say. I don't know if this would cause any problems.
A833 overhaulb.jpg

Removing the retainer snap ring, the drum would not slide off.
A833 overhaula.jpg
it will move back and forth, but not come off.
A833 overhaul.jpg
my build:
https://www.forabodiesonly.com/mopa...-now-let-me-see.541802/page-9#post-1974834683