Interesting, thanks guys. Its the weld points, or weld lines, that are hitting. They're just so darn close together. I read of an slk32 guy who reached in there with some sort of filing device and filed away a little on the thick weld lines or whatever they are exactly and that fixed it.

And can heater hose really catch on fire? And do the rear cats really get that hot? Oh goody I can drive around scared about a fire.