Re: painting an aluminum jon boat.
There are many many many posts on painting aluminum. Did I mention there were many many many many posts on painting aluminum? You said you stripped all the old paint off, so I assume you've gotten down to the bare aluminum. You really didn't need to, but since you're there, here goes..
There's many schools of thought and opinions, but this is what I did:
Yes, use the vinegar/water solution and wipe down the entire boat. Apply two coats of zinc chromate primer, according to the manufacturer's instructions. Now that primer is going to be mighty thick, but you can thin it a bit, again, according to the manufacturer's instructions.
I wet-sanded the primer lightly, and cleaned with a rag dampened with acetone. Once that's done, go ahead and paint with a quality paint. Personally, I used HMG Yacht Paint for the hull, and Petit for the topside (HMG doesn't have the variety of colors as the other mfg's, but is tough as nails, goes on like silk, drys quickly, and goes for about $22/liter).
Now, you can spray, roll, or brush. If you decide to roll, do a search here for "roll and tip", which will smooth out that paint beautifully. I feel HMG smooths out nicer with a roller than any of 'em, but that's just my opinion.
Follow mfg's instructions regarding dry times and wet sanding. I've always waited 24 hours before wet sanding.
As far as where to get the materials, the iboats store is nicely competitive, and has a wide variety of everything you'll need. You won't find HMG there though. Google HMG Yacht Paint and you'll be able to find a distributor if interested.
Barring all that, some guys get great results with 1 coat of primer, and some rustoleum. It all depends what you want.
Good luck
Rick