As a professional detailer I would dye the trim using this product http://www.topoftheline.com/trim-molding-dye.html

It comes with a fantastic cleaner, GR-40, and it alone can restore much of the color by removing oxidation, oils and years of grime. After this you can if needed, use the dye to re-new the color. use light applications and then seal it.

Hope that helps,
Anthony