wiring harness

Hello Jeepers, can anyone point me in the right direction in regard of acquiring a new engine wiring harness for a 3.7 V6 (2002 KJ, 4WD Auto-Trans) it seems quite a mission to find a source.

I've got a real puzzler on my hands and I'm hoping someone has an answer. The brake light control circuit on my Liberty (2006 CRD Limited W/235000Km) trips its fuse at completely random intervals ( hours or even days apart) killing the brake lights and sending the code P0504. I suspect a...