[C320-list] Cleaning engine cover

[Robert Seastream]

All:

I bought the SPM soundproofing insulation.  They say to clean the 
surface it's to be applied to.  Any suggestions on what to use to get 
the 'powderized rubber' from the engine belts off the inside of the 
front cover?  I've tried Windex, etc., but since the inside of the 
cover is a rough finish (unlike the outside), the rubber is turning 
into 'mud' and smearing.

Bob Seastream
'Intuition', hull 906