K, Looks like my Axle is approximately 13/4" long. sorry i cant be more specific. All I have is a ruler, and a good eye tonite. When measuring the axle, I closed one eye, and centered the string with my riser to make sure i was centered.

The distance between my limbs is 3/4"ID.

The distance from the inside of my limb tip (on the spacer side)to the CAM (past the string) was 1/2".

I know these measurements arent very close or specific but its ballpark and may help you a little bit.
Derek