Speedometer Gear Seal

Anyone have a diagram that shows the correct location of the inner shaft seal on an 904 transmission speedometer gear? I'm struggling with how deep to push the seal and the metal C clip. Looks like there are two shoulders inside the housing, thus two possible depths for the seal. I have a factory service manual for 1965, but I believe this is a later model transmission so the speedometer gear is different. Pics below show where the seal would contact the speedometer gear itself at the two 'depths' referenced above. When riding on the larger diameter step, the seal is quite snug and harder to turn.

IMG_2141.jpg

IMG_2142.jpg