I've been asked to paint a sign for a local business, it's galvanized... does anyone have any experience with trying to paint this stuff. I've looked all over the internet and found everything from white vinegar to acid etch to prep it for paint. I explained to the customer that it was notorious for not holding paint, but since it had been painted before, he thinks it'll be o.k.. He wants me to use all automotive products, so that it can be clearcoated when finished... I don't want to put my name on something that's gonna delaminate in a couple years. Any advice would be great.