No idea what WAN is...
Here is the complete service manual plus an annotated version of the collar replacement guide (kinda SB with extra comments, arrows etc). Hope it helps.
PS: 90% of 6910 leaks can be fixed with a simple spacer... unless the collar is seriously worn. Wish I knew that earlier. I had a botched warranty job that turned into a nightmare, then found out I didn't need to replace the collar anyway!