Id like a few opinions on the following. Ok so I am extending or shortening an existing lq9 engine harness for aesthetic reasons. Instead of cutting the wires into two pieces and soldering a length of wire into the cut two sections of wire, I went to auto part recycle yard, and dismantled a 98 Silverado wiring harness and separated all the wires that had pins on them in hopes of just having to do one joint/soldering spot per wire that needs to be modified. I went home and compared the existing lq9 harness with the wires I pulled at the junk yard, the lq9 wires appeared to be a thicker gauge with 7 thick strands. The junk yard wires are thinner gauge with thinner seven strands. My concern is having to much resistance in the circuits, in turn adversely affecting the sensors/injectors or the pcm in a negative way. Can I use the wires I pulled from the yard even though they are not the same gauge or will I cause electrical issues ? The girth of the wires are, .066 and .077, .077 being the lq9. I made a soldered connection using the different wires and measured the resistance, the meter showed 0 ohms. Another question would be why does the lq9 engine harness have different size wires for different components. What's the purpose of different gauge wires ?