I wouldn't do that. It may not cure property. I tried it and ended up scraping it off... My suggestion is to go to Harbor Freight and get a purple spray gun, drill out the 1.3 tip to 1.6 to handle the heavy primer and spray it. If your worried about the nooks and crannies, pick up a smaller gun. Their cheap and are throw aways. And if you still can't get in the small areas (then I might ask, how did you clean them out...) Then use a brush. Also make sure your primer is compatible to the undercoat or it will lift it.
Mike
