I want to do a resonator delete, but I don't want the cheap rubber pipe cap. Every decent plug I find says it fits LLY-LMM. I would think those should still fit the LB7, but I could be wrong. I would just slap a $3 piece of rubber on there, but I'm not sure about the durability of it under the hood on a 105 degree day. I guess the resonator itself & many other pieces under the hood are plastic and don't melt, but what are your thoughts? I'm sure there is plenty of information regarding this subject. Just a bit confused on those nice billet plugs only fitting LLY-LMM duramaxes. Not necessarily looking for anything shiny. This truck is far from show quality.