I just read a post on the quarter glass trim and got to thinking. (yes it hurts me to think

)
A friend of mine has repaired his successfully but he said that mine are in a little worse shape than his were. He just sanded the crap out of them then used trim paint and they turned out great.
I was wondering if there is such thing as a rubber or plastic filler that can be applied to this trim, let it harden then sand and paint.
Maybe through the eastwood co. or something? or a bodyshop supplier company?
thanks everyone