Assuming you are working with a Bosch O2 sensor wire, the 2 white wires are the heater wires, polarity is not important (12 VDC to one white wire, and ground to the other). The Grey wire is the ground (return) for the signal. The Black is the O2 signal wire.

A CIS fuel filter should be fine for your application

Ryan,

Where did you get the box used in the engine compartment for your wiring? Did you put the coils in there as well?

Joe A

I used a C2 or a 993 fuse panel box. I mounted the coils on the
rear engine mount as they were stock. I had to bend the
bracket a little but it worked out fine...

to answer your fuel filter question...I have used the original ones for the past 18 months with no problems. I also foun an hydraulic shop that made some fittings for the fuel lines.