Mar-x-ite sticks to everthing I've used it on, including green Ipe (a very oily hardwood) and everything I've used over it has stuck well.
wood workers are using Rust Lock as a primer on new wood, where others may have used either penetrating epoxy
or Red Lead in the past.
Both products dry VERY fast, and can be recoated almost immediately.
I'm not suggesting that you use any of these products without reading up on them or testing them.
I would use a couple of coats of Rust Lock over your cleaned-up and dried plywood, with an overcoat of whatever oil-based paint you have around.
I would not use any bleach to clean the wood, due to bleach being an oxident. In other words, it is a rust/corrosion accelerant. You want to see SS rust? Use a strong bleach mixture to clean it. I would be concerned about the impact of the bleach on any hidden fastenings.