Round Peg, round hole....there is no specific rotational alignment of the axle splines to keep track of....chalk, tape, whatev...not needed. There is no reason to record the position of the axle for replacing it...if the splines of the axle are engaged with the splines of the locker and the axle is all the way in (can be bolted on) then it is installed correctly. The "inner" seal is the seal just behind the hub out at the corner, not in by the carrier of the third member. It is a reusable seal that is not destroyed by removing/replacing axles...it is however easy to remove and replace with the axle out.
