Keeping it clean inside once it's done...

[Mt Man Chad]

I'm going over the small body panels in prep for primer, inner doors for new door skins, tail gate. I took the bed out getting acid dipped so I'll be shooting that in next week top and bottom.

My question is - on the bed side toolbox doors, I know they are the first thing to rust out. The one I am working with is very clean. What is the best way to clean and seal it so it doesn't rust in the future? In addition the door bottom insides before the skins go on.