I just did the third drain, so that I could swap out the o-ring on the drain plug. (Drain 1 was the pan swap. Drain 2 was the leaking gasket that I re-used...due to the instructions. Sigh. I used a new o-ring then, a brown viton one. and that leaks.)
Drain resulted in 4 1/2 quarts coming out. (Remember, the PPE pan I have states that it adds one quart to the capacity.) YMMV.
When I removed the drain plug, the viton o-ring was bound up in the threads. I am SURE that it went on smoothly. Shrug.
I've done 3 drain and fills. I have a new pan on (with a second gasket). The drain plug is on its third O-ring: first was PPE's green; second was Viton brown (from PPE) that leaked; third is another Viton brown (from PPE).
I also flushed the brake fluid. Thinking about coolant...