Transmission pr0n are my favorite threads. Good on you for tackling this project. Don't listen to anybody who says you can't do it or you need a clean room or it's best left to the professionals.
Those frictions are roasted for sure, bravo. Let's see both sides of the "thicc steel" aka the pressure plate. It might be scored hard on the one side. The snap rings show evidence of being burned, but they're totally re-usable so long as the clearance is right when you re-assemble it. You bought a rebuild kit with new steels, right? Also be aware that the front & rear frictions are the same diameter, but not the same thickness. I can never remember which goes where, I have to set up both stacks and then measure the clearance. If both check out then you're golden. If only one checks out then you probably have them in the wrong drums.
The scoring on the drum indicates that either your kickdown band is thrashed or there was some hard debris that got between the band and the drum. If those grooves can catch a fingernail then you might want to take it to a machine shop to smooth out. They can take a few thou off that thing w/o issue, the kickdown band is the only thing that cares about the outside diameter and the band adjust process will remain unchanged. If you can't catch a fingernail on the grooves then just send it. Nothing about that drum makes me think you need a new one, but a new one is (a) expensive and (b) could screw up your overall endplay, requiring a different set of thrust washers which you probably don't have. Replacing the drum is a last resort.
I also recommend a good cleaning of everything. Brake clean & then compressed air. Remember that there are tiny holes on the drums, shaft, pump, and case (including the piston bores)...brake clean all that crap out multiple times, then compressed air to dry. It's also a good time to get familiar with what holes & passages connect to each other. This is your one chance to clean everything out to start fresh, don't miss the opportunity.
