Then the retainer and snap ring. You can use a screwdriver to push down on the retainer and feed the snap ring in all the way around.
Once again be sure the thrust washer is in place, and install the OD ring gear.
Install the torrington bearing in the ring gear.
Now the already assembled OD and input shaft assembly can be installed. Set it in the ring gear and rotate until it seats.
Install a steel OD plate.
Then a friction.
On a stock trans there are only two frictions. So the stackup is steel goes in first, then a friction, then two steels back to back, then another friction, and last the backing plate and snap ring.
If you machined the apply piston, you can add a friction between the two back to back steels.