It should be ok, John. My only hesitation would be that you have to thin that paint with acetone, and because of that I'd want it to be very dry before anything was painted over it or maybe even up next to it...and I doubt I would ever be comfortable spraying it over acrylic enamel because acetone and acrylics don't like each other. Sorry to have overlooked that part. I don't think you need primer unless the surface is just too pitted or rough. That paint was made to allow spraying over rusty metal, etc.

~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end