My buddy works at Zeibart and I had him undercoat my k5 as well as do inside the doors, rockers, and tailgate. I got the work done for free, but I think it runs around $150, but not positive. The undercoating is black and dries to a fairly hard feeling, but you could still probably scratch the stuff off. I dont have problems getting it rubbing off on my while working on the truck. My floor boards had surface rust and some worse areas as well so before hand I wire brushed every thing I could reach and then put some rust converter on the rusty areas. I also had the inside of the frame rails coated, but painted the outside of them. I think their policy is also that after you have it done you can go in once a year to have areas toutched up to make sure it is still all covered. So, I would say its a good idea to do it on yours. good luck