I have midpipes that will bolt to your 1pc header.Tossing this out there but I don't think there's an easy response. I put the SR-S header on. Its good and dandy. However, while removing the 2nd O2 sensor the threads got all ****ted up and damaged due to corrosion/etc. on the sensor. This messed up the threads on the O2 bung and on the OEM midpipe. Currently I have the original O2 sensor with no spacer barely holding on with maybe 2 threads if that, kinda forced it in there because I didn't have many options when I was doing the work. I'm now throwing the P0420 code.
Due to this I can not secure a new O2 sensor with spacer in the same hole. I know, I know, get a die kit and rethread. That's on my mind and looking to give it a try, i have a mechanic friend that's looking for the 18x1.5 die to recut some threads.
But I'd like to replace the midpipe. That's the big question. As far as I know, you need to by the full race 3pc set to get the midpipe with no cat. I have the SR-S header already and can't seem to find just a midpipe for sale. Most are designed as a package.
I could also have a new bung installed on the OEM exhaust but with that damn shield over the entire midpipe and the overall shape of the midpipe I'd like to replace it while I can.