good work there mate,

as far as the rust thing goes with the cleaned metal you can have them zinc or nickel plated at the electro-platers or what I do with some of the lock down bar mechs is spray paint with a good quality clear lacquer using a pressure pack. of course if you manage to chip or scratch the clear lacquer off it will start to rust again.

I was going to try an experiment with some car wax and rub it all over the metal, let it dry then rub the excess off to see how that goes but I haven't got around to it yet. I will let you know how it goes.