My new (bought used) bike had corrosion on screws on handlebars, especially the screws holding the armrest for TT style bars.

I replaced those Allen head screws on the bars but the screws holding the arm rests are no easy to source, so I just removed some rust rubbing them with a rust cleaner and lightly oiled them with machine oil and put them back.

Also had aluminum housing of the shift levers corrosion due to sweat from hands (I talk of those shift levers on the tip of TT bars, not briefter shifts on brake handles), also cleaned them to make them decently looking again but I am wondering if I should smear them with some grease to protect them from sweat, since I too do sweat. I try to wipe sweat drops from my chin on my forearms when I ride but something still drops down...

What kind of oil or grease do people use, if any, to smear on the screws and shift lever housing?