Need help with a Flat file re-paint....

[Mapman]

So i need to repaint the flat file I purchased a couple of weeks ago. I started sanding the outside of the cabinet, and the front of the drawers, I was just going to repaint the outer areas, but now I am curious if I should just repaint everything inside and out, or possible just prime the inside to stop any of the small spots of rust from spreading. Honestly I'd like to do the least possible when it comes to painting, but also don't want to damage any prints if I don't deal with the interior now.

I do plan to line the drawers with foam core, create a wooded base, and top. OH and this doesn't need to be display quality, it' s going to be in the basement.

Thanks!