there should be double nuts on that post so the first nut [w/lock washer] holds the post, another holds the wire .... if the winding wires aren't badly gouged or actually pressed together they shouldn't be a problem, but not much to be done in any case .... for the slots, just make sure there's some depression there and no ragged edges to damage the brushes - commutator looks like it may have been previously turned down
Bill
