I've been installing two old Jackson passive humbucking pickups on the Aria Pro II guitar. I had to tear out the shielding to fit them in and scrape/file away some wood. The Jackson pickups must be bigger than the Aria Pro II pickups; the meter indicated that they are about twice the number of ohms in spite of their age. I had to extend the wire; I've re-installed the Jackson pickups enough times to have cut a bunch off the ends. I didn't have four-conductor wire, so I made some with separate colors of single conductor wire plus one strand without insulation to conduct to the kitchen foil wrapping I gave it. I got heat-shrink tubing to wrap it all up. My homemade four-conductor wire was too thick for the existing wiring tunnels, so I had to enlarge those first. By the end of the session, I had threaded the homemade four-conductor wires into the control cavity awaiting hook-up.