Jim:
There is now a product specifically for cleaning before paint. It is called wax and grease remover and is available from auto paint supply stores. I use it rather sparingly by putting it in a squirt bottle, spritzing on the surface, then wiping off with a clean paper towel. It is important to wipe it off before it dries to get the contaminants off. I usually work a 2'X 2' area at time to ensure it doesn't dry before it is wiped.
I hope this is helpful.
Regards,
Steve
New Orleans
