I'm using the FT200 Finish 1 Surface Cleaner product sold by Sherwin-Williams through their automotive refinishing division (probably not available at their home paint stores). I guess it was expensive at $20/gal, though I've only used about half a gallon so far doing wash-sand-wash of the new sheet metal I'm putting on my bus. It's all new, which is to say 10 feet high and 38 feet long, both sides.
I like that this product doesn't melt nitrile gloves the way acetone and xylene do, yet they advertise it as "FT200 is a fast evaporating, mild solvent wash used to remove wax, oil, grease and silicone contaminants from all O.E. finishes, Acrylic Lacquer, fresh or uncured enamels and all sanded surfaces." Wipe it on with one rag, wipe off with another before the product dries.