Hi, I also had a leaky 54 Alumacraft model A,with worn out paint and bare spots. 2 years later, the paint still looks new, and the boat is still bone dry.
Here are the steps I used to restore it back to as close as I could to the original factory grey finish:
1. Power washed both floor and bottom.
2. Applied Gluvit to all seams and rivets on the bottom, and on the inside.
3. Applied inside two coats of Pettit Metal Primer 6455 / 044 (750339).
3. Coated the primer with two coats of Pettit EZ Decks – Non-Skid Deck Paint (755704DNSPGP).
I have included a few shots of the process. I was very please with the results. Did all of the painting, and prep work in the middle of a NY July temp in the 80’S.
Hope this helps,
Bob D