I am sending my new CMI elbow tops back to CMI to have O2 and EGT sensor bungs welded into them. My question is what is the O2 sensor bung thread? I think it is 19x1.5mm and what is the EGT bung thread? I think it is a female 1/8"NPT.
I am having the O2 bung welded facing front just above the water input on the collector and the EGT bung welded on the back cylinder pipe next to the flange on the bottom before the cool coller. Any thoughts or suggestions?

im pretty sure they are 18x 1.5

i should have read on, you cannot put the o2 sensor where it can get wet. if you have water going into the exhaust you need to get it as far away from the water as possible.