My. Two cents. You can't paint without keying it. I used Brown 3m about 300 quite corse. Easy fast leaves a great key. Six hrs before painting wipe with metho. Use a two pack. finish is superb. I use a 1 mm nozzle hvlp touch up gun. Perfect for 90 percent and a little slow on the big stuff. Fine finish and you can keep the primer to minimum.
Going to all that trouble worth another 5 mins work with two pack Just be careful not to loose your part numbers.
Lyndon