I'm with the acid guys. Autobody metal prep (phosphoric acid in H2O solution) is formulated to remove oxidation without eating the base material. I have cleaned and restored many old and seized SU carb sets using a metal prep bath. Degrease first then soak the surface to be cleaned - time works best to get all the oxidation off but you could substitute some brushing with a nylon brush for a dunking if the parts are too big. Wear safety goggles and watch the clothes. It will eat denim and burn skin.
A hot water rinse works best. Works well even on old airhead engine cases!
The more I learn about women, the more I love motorcycles!