OK Alum washers and gasket. I have a couple Liters Valvoline 80W-90 gear oil. Is that good enough or should I have a different weight? Can I safely rotate the trans by running the motor with it open a few rotations if I have the wheels off the ground? I was thinking the ball might fall out that way if not by draining it. i'm going to put a magnet inside by the drain when I close it back up too.