Actually it means stranded copper wire, not solid. You would need to take the conduit off the factory harness, and remove any harness tape to access the wire. The plug-and-play adapter should have come with the wire, and a terminal on one end, that you place into the C100 bulkhead after removing the resistance wire. Then, within about 6 in. from the CCCI connector, the resistance wire splices into a regular piece of copper wire. You cut it off there, splice the new wire into it, then button up the harness again.
PS Use harness tape, not black electrical PVC tape.
PS Use harness tape, not black electrical PVC tape.