This is where I write about stuff I find interesting.
For future reference, here is the Hydro-Gear manual for servicing their 326768 BDU-10S transmission.
https://www.hydro-gear.com/download/210-1010s/#
or here:
https://drive.google.com/file/d/1hv2nz2seT1RsteBFH0Y48am35c1eAM0r/view?usp=sharing