Hoping to get some help here... My son has a 1999 XJ Classic and CEL came on the other day. Popped the hood and notice that the plastic wiring rail harness that runs along the valve cover was melted - along with the wires running through it... See attached pictures. Obviously need to replace the rail and wiring but not sure if the wiring harness is completely replaceable as a single unit...

Any help or guidance here would be much appreciated. Not sure what caused the plastic rail to melt. The jeep is running fine but expect that the melted wiring to the fuel injectors will be an issue soon if we don't get this replaced.

Thanks for any help.