I've got a couple questions about my swap. It's a 2000 GSR into a 1998 DX Hatchback. 1) Can I use my stock exhaust and just have the muffler shop connect it to the GSR cat? I know aftermarket is better, but I just need something done temporarily before I have enough money to get a new cat-back. 2) Is shielded wire required for the knock sensor and CKF wire? Have any of you guys thrown codes without using it? Thanks in advance!