[Walt Fricke]

I agree. 0.006" is simply not worth worrying about. We aren't talking piston to cylinder clearance, or some gear lash, or whatnot.

Absolutely do not use an aluminum washer. The factory (and all of the aftermarkets which come with replacement stud sets) washer is a hardened steel.

If you are really freaked, use a good quality thin steel washer and be done with it.

Even better, purchase a flange nut. You can get these with a 15mm wrench size, so you can get a socket over it down in that hole. Usual M10x1.5 thread size. The beauty of going this route is that you will never have a problem if the stud is a bit tall. The socket won't push out like Henry describes an Allen in the stock barrel nut can do.

I think that everyone doing a rebuild should toss the barrel nuts and use flange nuts. Unless they buy the Supertec kit, of course, which comes with all the needed hardware - including very nice 12 point flange nuts.

But in this case I'd just keep on assembling the motor and not worry at all.