RE: Replacing the voltage regulator
BTDT.  As for the brushes, just be careful.  But be aware, you may need a
little right angle Phillips screw driver to get to one of the two screws
without moving things.  I posted this picture a couple of years ago and have
left it up:
<https://picasaweb.google.com/starwagen/DonTLeaveHomeWithoutEm#>