Shift kit arrangement looks good. How you have it mounted to a table makes me laugh because that's exactly how I did my first transmission.

Couple methods for tightening up third clutch pack. One is going to be to use a razor blade to remove all of the friction material off of an outer lugged 3rd steel/friction (used one that you pulled out) or to take one of then.055" plates out and use a mid 80s 440T4 3rd steel which is. 090" and puts it around .030-.040" clearance.

What is this super secret snap ring they ordered?