Corrosion on aluminum threads

Maybe try the lemon juice binager thing to soak then maybe take a something like a plastic sour cream container with some sand in it and shake roll them around to sand scrub the bolts/ screws clean and bright.

Then check out dielectric aluminum grease as a protective coating .

https://allthingsaluminum.com/cleaning/how-to-clean-aluminum-corrosion/

( for a example)