Ouch!

The idiots at Wal-Mart not only overtightened the nuts but must have cross
treaded the one you stripped out the stud on trying to remove.

The studs are cheap, but may require the hub be removed to replace.  I
almost hate to say it, but you need to go back to Wal-Mart and make them
(find a manager to do it) remove all the wheels and check the other studs.
They should replace the damaged one, and make sure they use a torque wrench
to re-tighten them!

NOTE: do not try to remove the others without an air impact wrench, you will
most likely damage them all!

Stuart MacMillan
'84 Westy w/2.1