have a 97 gsr and i just got a rsr header for it. The only problem is that the header doesnt have an o2 bung to put the o2 sensor in. What can i do so this wont be a problem? Could i just gen a hi-flow cat and have 2 bungs on it or would i have to have one welded onto it? I was planning on getting a hi flow cat soon anyway so which way would be cheaper/easier?