had to remove rear drive shaft to facilitate hydraulic pump replacement.Now that I'm ready to put rear drive shaft back in it fits in but doesn't seem to go forward enough?The joining sleeve that has a cotter pin through it won't work in either position?(explanation)position (1)the rear drive shaft sits too far rear-ward so as to not allow the cotter pin entry. position (2)if the sleeve is fitted the other way around then because of the cotter pin location the drive shaft would then be able to "float" too far rear-ward? I'm wondering if the shaft or mating component that the "front" end of the drive shaft meets has somehow moved rearwards? I don't see how. There must be a simple answer?