d series turbo question
 

hi I've begun turboing my 96 civic hatch and ive just got a couple questions,
first one is about the o2 sensors, there is a place for one at the bottom of the downpipe, yet no where for the other one to go, am i supposed to have it attached in near the top of the downpipe? also where does the stock IAT sensor go, there was a place for it in the old intake pipe, should i just drill a new hole put a grommet and pop it in?
any info would be very helpful thanks.