When I painted my truck, I washed it with Formula 409, and then wiped down with a paint-prep wash. Basically acetone with other solvents added. during this stage of the process I found my truck had previously been painted red. Wherever any red was exposed, the red became brilliant. It really brought it out. You could wipe down with acetone in a hidden spot to see how it reacts. Just a quick once over, don't linger or it may remove paint. Could also work to clean the gold.
