[Vwdiesel] 93 EuroVan - alt problems continue

[Rolf Pechukas]

a couple weeks ago I posted about a blinking alternator (battery) light
several wise and experienced members of this board directed me -  
correctly - to the alt brushes
I removed, cleaned, reinstalled them
problem solved

but now
blinking batt light again
removed brushes again
uh oh, they look fine
re-installed
external connections also look good

there are a couple small metal tabs sticking out at different angles  
from the brush assembly
those must make contact with something
mine are kind of crudded up
important to clean these?
how to do without damaging anything?
anything else to look for?

currently stranded at a coffee house hoping it warms up out there - 4°f
battery just not cranking fast enough to turn over

thanks for any thoughts
-- 

Rolf in MA