So, step 1: clean the transmission. Â Engine degreaser, brash brush, some elbow grease. Â All clean. Â The main thing to watch out for here is to close up the speedo opening, and the top of the turret. Â You don’t want to get any water down in these. Â I stuffed the openings with absorbent towels, and then taped over the opening with 1 1/2″ masking tape. Â Then I was careful to not direct the water spray AT these taped over openings.