Nice investigative work sir.
I have never had my hands inside an automatic and it would have taken me forever to work up the courage to tear it apart.
Its not my first time with a auto, and it certainly wont be the last.
Thus far ive dealt with 700r4, 4l60e, th400, th350, and a 4L30e.
Im not an expert by any means, but the general.... eh... red tape of it all, i cut thru and conquer the lore surrounding automatics
Example being, i did a very intentional halfass job on the 4l60e in my s10 mud truck after i grenaded it.... and thus far it has survived straight, outright, brutal PUNISHMENT.