FWIW, I've had ProFab tow flow up pipes and then 2" headers and up pipes on my 06 LBZ with a diamondeye DP and didn't have to dent the DP for either.
Was the passenger up pipe flattened for clearance. Probably since these are designed for stockish trucks.
I think Rick makes great products, just pointing out the reason why some people need to clearance their downpipes.