I received my flap positioning system with automatic elevator trim (FPS-Plus) from 'Aircraft Extras'. I was going to put it under co-pilot seat and had run most of the wires I decided it would be better behind the panel, so I removed the wires I had run to under the seat. I made a mounting pad for the FPS-Plus to go inbetween the panel ribs and started to run my wires again. It was preferable to keep the wires away from the strobe wires so I ran them down the other side of the firewall and along the opposite side of the tunnel run. With the cable marking, I used the idea I found on the internet (Dan's I think). First printed off the labels I needed in very small font, placed them on the cable and had clear heatshrink over the top. This is very time consuming but it looks good, very professional and most importantly I know which cable is which.
