Rust preventive suggestions for rockers

[PlanZero]

So I thought my Tsi was rust free until today I lowered the jack and some rust fell out of the rear jacking point on the rocker panel. I stuck my finger in the hole under the sideskirt and there's nothing there. I found a gaping hole the size of my boot under the sideskirt. Needless to say I'm devastated.
Anyway, I realize that I need to cut the rust out. Problem is there is also a rusty coating running the length of the inside of the rocker. How can I treat this? I obviously can't apply por 15 properly in such a tight area. Replacing the entire rocker is out of the question right now.
And how to prevent future rust in this spot? For those of us with sideskirts there are what I assume are drainage holes running the length, which allow salt to get trapped. Blocking them off completely will prevent drainage. Suggestions? I'm ready the spray some great stuff crack sealer in there! Help!

 

[oneslowwdsm]

Cut out as much as possible. Try getting a wire brush in there, power wash, and wait till dry. Find a paint brush that fits and try getting some POR15 in there. Then maybe use some rustoleum and undercoat. This is an area that is hugely affected on most 2gs so don't feel so bad. You wouldn't believe how much of the rockers I had to cut out on a previous 2g and had no problems drivability wise.

 

[PlanZero]

Oh believe me I know. All of my other dsms had it, and I was happy when I purchased this Tsi with no wheel well or strut tower rust. As of right now the hole is about fist size, but I know once I start cutting it will at least double in size. I'm considering just cutting and wire brushing the hole, then spraying rustoleum as much as possible into the inside of the rocker, treating everything I can reach with a brush and POR and just leaving it. The sideskirt will hide the hole. There's no point in trying to patch it when it's impossible to remove all the rust inside the rocker. I have a ton of body panel clips, so I can just periodically remove the skirt and clean the hole and retreat as needed.
I realize the only perfect solution is to remove the entire rocker and replace it, but I have no welding ability and finding a rust free donor car in PA is near impossible.

 

[PlanZero]

OK so here's what I did for anyone that's interested. After grinding away all the rust I was left with a hole about the size of an index card right next to the jacking point. Unfortunately I could feel that the rust had eaten away an even bigger hole in the inner layer of metal. Since I wasn't welding, it seemed ridiculous to cut a bigger hole on the good outer metal. I removed as much as I could and sucked out the dust with a hose attached to a shop vac. Thankfully I could feel with my fingers that the rust hasn't reached the wheel well. I got some rust reformer and sprayed as much as I could inside the panel in 4 coats and let it dry overnight. I then used a sponge and POR 15 to coat the inside and outside of the hole. After the second coat I took 4 pieces of fiberglass mat soaked in POR 15 and gingerly applied it over the hole, going back every half hour with a foam brush to make sure it was adhering properly. After letting that dry overnight I sanded the area with 220 grit and two coats of primer. Then added two coats of undercoating applied with a sponge. Once that was dry I slathered the area with permatex black silicone. I also used that around the plastic screw brackets on the bottom and plugged the extra hole on the rocker. I used all new plastic clips and new 3m tape when I reattached the skirt.
I realize this is only a band aid for cancer, but I hope it will last a few years until I cut and weld a whole new rocker.
Also, after seeing how much crap accumulates in the bottom of the sideskirt I'm going to make sure I aim the hose inside the drain holes when I wash her, especially in winter.