Maytag two belt washer overhaul

This is my first visit to the forum, and I arrive here in hopes of finding another old timer like myself, but with experience with the A112 Maytag. My unit was purchased back in the '80's and it has never failed to wash as it should. Few years back I gave a new set of belts, but that is it.

Now, recently I notice that the spin cycle doesn't seem to get the water out of the wash load as well as it used to. Also, I can hear more noise (rumbles) when the spin cycle starts. Therefore, I decided to give the tubs new bearings and seals, and that has led me to go further and just give it a general overhaul throughout, with new seals, bearings, and hoses.

The effort is just getting underway, as I wait for the necessary tools to arrive, in order to take off the tub and brake nuts. My very first and only such attempt is just starting. Looking ahead though, I have a question for the forum. I plan to open the transmission (older style - not orbital), clean it out well and button it back with new oil and seals. I believe I can see a way to get it done, just looking at the parts illustrations on the Maytag site. My big question at this point, is how much oil should be in the transmission when I close it up.

Really wish I had a service manual, but couldn't locate one.

Any thoughts will be greatly appreciated.

James