The tunnel protectors are already extended past the back of the rear heat exchanger, at least on my 2007 rage they are, and the studs still tear up the heat exchanger. My solution was to cut a couple pieces of hyfax a little longer then the heat exchanger, and rivit them to the protectors already there. You have to grind down the inside lips of the hyfax, so you can slid them over the existing protectors. I actually put two small pieces on each side, because if you look at the protectors that are on the sled there is a slight bend a little bit in front of the heat exchanger. I started one piece where the bend starts, that way there was less of a chance that the track would rip the hyfax piece off. Then I cut another short piece and slid it ip against the first piece and rivited it in place. I also grownd off a little of the top off the second piece of hyfax where it butts up against the first piece, so it is a little lower, this wat the track will not hit the front edge of it. I have 2,500 miles on since i did this and no more problem with the studs hitting the rear heat exchanger. Hope this helps.