Air Fuel Ratio and Oil pressure gauge hookup

[boarder445us]

I was wondering if anyone has installed any of these guages in any car. I have a 97 240 sx. i have power to these guages, but the A/F needs to be spliced to a signal wire off of the O2 sensor, which has 4 wires and i dont know which on to splice it into. Also the oil pressure hookup looks pretty complicated. If anyone knows how to hook either of these up i would appreciate the help. Thanks.