In case anyone was wondering, I got this fixed. Just surface rust, nothing serious. Just pulled up the rubber seam seal, swept out the loose rust, and sanded out the bad metal. After I cleaned the bare metal, I used a rubberized undercoating spray that I ordered out of JCwhitney. I ordered four cans of the stuff, and there was plenty left over. The can suggested that the spray was good for sound insulation...So I decided to try it out. I'll post pics if anyone wants, but since I only have my door / interior panels in, it just looks like bed liner sprayed on: interior floorboards / footwells, the rear seat bench, and the spare tire well. got in and started 'er up-huge difference in interior noise--can't wait 'till I put my pad/carpet/seats in...it'll be quieter than a damn Lexus.