I need help with my O2 sensor placement... I already know to place them as close to the collector as possible and to clock them so they can drain any moisture that could build up but as far as depth into the pipe... I assume to place them so the tip is as much toward the middle as possible?

Right now I think I messed up by having the bungs sit on the top of the pipe and am getting wide swinging O2 voltages... Looking in the pipe I can see a smidge of the veins are covered like it isn't seated into the pipe enough... Before I redo the O2 adapters I would like opinions on where the tip of the sensor should ultimately end up when all is said and done.