Looking for suggestions on aluminum jack plates that where anodized black. The boat stored inside through the summer and they turned purple/bronze within 2 months. I have been told can't re-anodize, thinking about epoxy primer with urethane top coat, or powder coat. What does Mercury use on the drives? Any ideas appreciated.

I haven't had any luck getting anything to stick over Anodize , for a reasonable length of time in a Marine environment. They can be stripped and re Anodized.... looks like **** though.
I would have them blasted and use a good epoxy primer and urethane paint to cover it . Rick @ IMCO says they use Axalta IMRON MS600 on all their drives now .

I had a bunch of pulleys stripped and powdercoate d that were hard anodized

The bond rail on my boat was silver anodized. I sanded it with 280 grit to give it some teeth and then sprayed it with "SEM products self etching primer". It's a professional grade product that comes in a spray can in several colors. In my case I went with black. It's made to adhere to steel , aluminum, and stainless. I then sprayed a single stage black urethane over it. It seems to have worked, I don't have any scratches or nicks yet.

They would need to be stripped and redone, this was purple anodized then stripped and P coated.

Powder coat is fairly easy and durable and I'm going to be doing my plates soon.

Am working on cleaning up the engines now. These parts were all sand basted, coated, and also had a coat of clear powder coat put on them, too. Hard as a rock and I couldn't even scratch them with a nail.

I'm in the process of refinishing my Latham trim tabs. Latham, anodized and then powder coated them. Are you guys saying you can't powder over the anodization?

I had no luck with anything on aluminum after it was anodized. The best thing I got to work after stripping off anodized coating on the rear vents on my AT, was Rustoleum with simple prep in the garage. I tried having them powdercoated, but it didn't last a full season. I think forged parts do better than cast parts.

I had my drive lowers and 380 tabs painted with Gloss Black Epoxy at a body shop, and that worked really well.