I have sealed the edges of the plywood with epoxy and then painted it. I had thought to apply some anti-fouling to it, but decided it isn't necessary. Most of the time the plate will be out of the water. It will only be in place, under water, when I am actually sailing. I have oiled the oak parts with linseed oil and covered teh two brackets in the boat first with epoxy and then with copper tape, set in the epoxy, so I hope it will stay on. They will be permanently under water, so need to be anti-fouled.
I have finished the superstructure painting outside of the cockpit, and it looks OK. I might apply another coat on the stern deck where it looks a bit thin. I have got to decide whether to do the hardwood next and then paint inside the cockpit or vice versa. Decision decision. I want to replace the main sheet with a longer rope and the lazy jack "topping lifts" but I will wait until I can get to a cheap rope show before I do that. I won't need them until April