The first step in rebuilding the older transmission was taking everything apart.
A lot of people are good at taking things apart. Fortunately we have some people that are pretty good at putting things back together as well. Here the upper section is suspended while the planetary gears are being chemically washed and cleaned. Suspending the section allowed gunk and grit to be washed out of the bearing races instead of being driven further into the races.
The lower section has been cleaned and all gearing now rotates smoothly.
Each piece of the housing is cleaned and gears and bearings are cleaned and lubricated to restore smooth operation.
And individual parts are laid out so they can be cleaned and checked.