I took wheels off gave em a coat of spray can automotive clear when new. Im not sure what metal is used for the body/housing, but assuming it’s stainless. I had bilstein 5100 leveling shocks on my last 2 GM trucks- first set wound up getting oxidized/rusty overtime- not like raw steel flaming rusty- like rust stains- turns out those had 400 series (CR steel- no NI content) stainless housings. They won’t rust through, but looks crappy over time. I assume if I really cared you could probably use some metal polish & bring em back to better than new- but not really worth the time on a DD truck- so that’s why when I ordered a set for my 2nd truck I use the rattle can clear before installing.
Again- not sure about these fox shocks tho, if you wanna check see if there’s magnetic draw if yes then 400 series if no then 300 series & wont oxidize/pit
another good coating product especially for bare AL/stainless stuff (and honestly anything under the hood wires-plastics-rubber included) is Yamashield marine protectant (used to be called boeshiele T9) - it goes on clear & dries to a slight sheen - is not as permanent/heavy duty a coating as Amsoil HDMP, but it won’t discolor anything, can be removed if need be, & is also good as an undercarriage or Underhood “dressing” like Griots undercarriage spray- car show dudes use it, but main application was for Yamaha marine engine/crafts