I had no idea they were so accessible. I'll hit a NAPA before the leaves start falling. Probably give it 2 or 3 coats - it's an 06, currently 113k miles, and ZERO rust...but likely never been treated before. I'm the second owner, and from what I heard the first owner never offroaded it or used it like a Jeep (I'm making up for that lol). So far I've undercoated underneath (after surface rust conversion), bedlined the entire interior, and tossed the carpeting (all it does is hold moisture and grow funky smelling mold anyway). I did space the skidplate that holds the transfer case, down from the frame by 1/2" - these love to rust the frame out where the skid plate attaches because moisture gets between the two pieces and just...stays. But my hope is, by spacing the skidplate down using washers, and creating airspace between the plate and the frame, it won't rust. I make a point to hose off underneath whenever I get it gunked up...but I'd really like to treat the insides of the frame rails for peace of mind.