^ hey, that's my hand writing
mr_240sx, the color is exactly the same as S13 Sr20det wiring harness.
so you bought an s13 without an engine and harness? go to the junk yard and cut the gray and brown harness off. You need that to wire up the s14 sr harness. You also need to cut the cluster harness plug too. (SOHC and DOHC) are both different, get the right one for your car's year.
What you do to the s14 harnes is cut the wires from the F3 plug (the blue/white plug that is next to the ECU. The 6 or so wires you cut will need to be pulled through the harness and ran towards the battery (front/right fender) area. This is where you solder those two Gray and Brown harness plugs.
The red and red/black will need to be extended to that same fender area.
ALL colors match up btw.