Rich:
"I guess the easiest was to drain the transmission is through the fill as you would do when draining the oil. Using a
pump?"
Yes. Use the same
pump with which you withdraw the oil in the engine. You will not be able to remove all the transmission fluid, so note about how much you remove and then replenish that amount, not what a manual tells you is the total capacity. Run the engine, in/out of gear a few times, then shut down and in the next few minutes check the level again. That''s when the measurement will be most accurate.
Jack