Found this in another post on here from Mark_V......:
1] scuff sand entire boat with a sanding sponge to ensure it is smooth
2] scrub boat with soap and water and rinse well
3] wipe down THOROUGHLY with white vinegar and let dry
4] paint Rustoleum (thinned out some) with a good natural bristle brush - two coats. Let dry well and then wet sand LIGHTLY with 400 wet and dry paper. Tack off dust etc with a clean cotton rag and paint thinner, then brush on third and final coat with very clean brush
Since this will be a hunting boat and ran into sawgrass/brush and everything else on the water, these are my next steps. the outside of the whole boat is white now, Ill be goin for a green, brown, or tan on the outside. Im hoping to get it off the trailer and start sanding away this weekend. Maybe even today.
Majority of the white paint is on it pretty good. Only small areas where I can see it is bubbling/peeling. So I will be hitting those areas good and feathering out. Ill probably hit around every rivet good too. Ill post pics if I actually get to it. Two little girls under 3 keep me tied up pretty good on the off days.
Yes, you can use ZincChromate(ZC) OR SelfEtching(SE) as a light dusting coat over bare aluminum
I don't know anything about the camo paint you've chosen, but, IMO, most paint jobs turn out (and hold up) much better if you prime w/ a primer from the same maker as the paint, using what they'd recommend as best under their paint, in as many primer coats as they recommend.
I don't think you can paint prep too much before the ZC/SE or between primer and paint, ALWAYS following the re-coat recommendations for each type of paint: ZC/SE, primer and topcoat paint.