A.) Somewhere on the rear fender? B.) As close as possible to the bolt that bolts the rear fender and the sub frame together? The reason I ask is because I was measuring at the same place everytime on the rear fender. Turns out that my sag was off, by alot. I knew the manual said to use the bolt but I figure that it wouldn't make a difference if I just used a pin mark 3-4 inches to the right of it on the fender. Especialy if I used the same spot every time. I found that I was off up to 8mm on my bike, and on my buddies bike who has it sprung for a heavier rider, was off almost 12mm. Just something for you guys to think about and try the next time your having issues dialing in your suspension.