I have a 1977 K5 Blazer and had to take the hubs completely off so I could get the axles out. Im not sure which way the large gear with teath that meshes with the inside of the hub and is the first part behind the snap ring faces. One side of the gear is flat and the other has a flange that protrudes out about a quarter inch and dont know which side faces the snap ring. When I took the hubs off one hub had the flat side of this gear against the snap ring and on the other side the side with a flange was against the snap ring. I had some work done on the front end awhile back and think they must have put it in backwards......thanks in advance for any help....Dayne