I had one. Got a nicer roller processor, and the rcp20 went to the tip. Fill the tanks to the notch line before adding the roller was the way I recalled it. Less than2L, but exactly how much I cannot recall. The middle tank, for stop is smaller capacity. I would suggest mixing a buffered stop for that bath.
The first tank had the thermostat, and the pump to spray the developer.
Capacity is 8" wide. No wash. so wash after the print comes out.
Withe Kodak RA-RT mixed to replenisher strength, I add 20mL per 8x10. I do go as long as 100mL before replenishing with no visible effect.
I hope this gets you started.