Inside of metal panel coating?

Hello to all and thank you in advance for your input.

I have to put my quarters back on my Barracuda fastback and realized that the inside of the panels are bare... is it ok to leave them bare or do you all use any kind of coating? I would assume that I should paint them: primer/base coat, before installing them to prevent future rust... The same is to be asked about my lower windshield cowling, or the portion that the wipers come up through.


I did primer/base coat. Cleared the whole trunk as best I could after install.