No-ox-id, period. Tiny amount, apply to threads, screw together and apart a few times, wait a full 24 hours before using and you're good.
Noalox, as already pointed out, is a conductive grease mixed with zinc powder. Designed to prevent oxidation of aluminum joints. The grease dries out over time also. If you clean the old off and reapply once a month or so it'll work fine to improve conductivity on any of the metals our mod are made from. But way too much work when you have No-ox-id as another option.
As far as a general purpose protect the finish product, I'll suggest renaissance wax, originally made for the british museum, Amazon among other places. Next suggestion, mothers mag polish, any auto parts store.
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