Learned a tough lesson today. Don't use ACETONE to clean prior to priming. I ended up using Denatured Alcohol instead, but think I need to find an even better cleaner / de-greaser since I still had some spotting during priming. Some of the problem may still be my spray technique, but I am targeting the cleaning agent first. Two full booths worth of metal on both sides (4 spray sessions). Also, make sure to clean the spray gun in between sessions. It gets complicated once it starts to clog in even in the slightest bit.