I have stage 1. I have read here that one of the O2 sensors is no longer used with stage 1. Makes no sense to me, but I would guess it would be the one after the cat. Would this be an unsutable place to put a wideband sensor? Or should I just pay the $80 to get another bung welded in? I am going to be upgrading my exhaust in a few months and think it a waste to pay twice... Thanks.