The bike is a mid-80s MB-2 with 130-mm O.L.D. I put a 7-speed HG cassette on the UG/HG freehub (not original) and the inner plate of the bolt-on axle stop rubbed against the surface of the lock ring. I removed the axle stop and, using the scuff marks on the dropout and my eyes, was able to align the wheel with very little difficulty. In the highest gear, I have a couple of millimeters of space between the chain and the bottom of the seat stay. Shifting and everything (i.e., no rubbing) are fine with the bike in the stand. I haven't been able to test ride because I'm nursing a knee injury.
According to what I've read here, wheel alignment may take a little more time, but there should be no safety issues with the axle stop removed. The XT QR (it's an XT hub) is quite snug but not overly tight. Do I have this right?