Saving the rockers

[CaptKirk]

Well, my '97 X, which was totaled was in perfect shape besides the rockers. The design is poor with holes in them for the skirting and all the water sits inside the rocker.
Well, I bought an '01 Sport Trac and the rockers and the rest of the truck is perfect. What can I do to prevent any rust on or in the rockers. The SP has the same plastic skirts the '97 did.
Can I spray anything inside the rockers that would stop rust and not make anything worse if rust has started inside them.
Thanks for any advice. I want to try and keep this one from rusting.

 

[kert0307]

I look over the underside and fenderwells of mine every year, sand off any rust, and repaint it with undercoat paint. The only way to see what's behind the plastic is to take it off tempararily, sand, paint, and put it back.