tune pipe
we had a guy at our field do something like what your talking about i don't think if the tuned pipe touches it's much of a problem
the header is a differnt story what he did was take epoxy and coat all the areas he thought was a possibilty of touching he never had a problem.you could proberly get some of the aluminum
tape like they use for burglar alarms and put some where the pipe might touch i would just becareful not to put it where you didn't need it,you could shield the fuse where a radio signal might not reach the radio and kill the signal,but i don't think small amounts just where is needed would be any problem.
roy