I live in MN so I know that rust will liekly be the killer of my car. That being said I'd like to fend that off as long as possible.

In the rear fender area the exterior body metal is bent back to give the smooth edge of the wheel well and is connected to a second sheet of metal. I'm not sure if it is spot welded or what but I can tell there are gaps in there where dirt, salt and road grime tend to accumulate. I try to flush it with a hose but I've noticed slight rust stains coming out of this area.

The only thing I can think of would be to spray rust converter into the gap between the 2 sheets of metal and be careful not to overspray.

It's only an 08 so not the best thing to see. Anyone have thoughts on how to address this?