I cannot take credit for this idea. I saw it on the rear cargo light install thread. I sourced my cargo light and pigtail from a part out (Thanks Arcteryx).
What I did,
Remove cargo light behind second row seat.
Remove D-pillar seatbelt on driverside and the plastic.
Remove caps holding up headliner and separate the headliner at the rear cargo hatch.
Remove grab handle and plastics from rear hatch.
Allow headliner to droop a little in order to run wire (2 separate 18G) to rear cargo light
Run wire from body to rear hatch utilizing rubber "conduit" already in place for rear defrost and wiper motor wiring.
Use vampire clips to attach new wire to existing wire for rear cargo light.
Cut hole in plastic shroud of rear hatch to mount cargo light to.
Use a small piece of wire run to the cargo light into the light and secure wire using a small round eyelet wire terminal.
Test light after ground wire attached to mounting bolt. (I used one of the bolts holding the wiper motor to the rear hatch)
secure light to plastic shroud.
Re-install shroud.
Re-secure rubber conduit to hatch and body opening inside the "door jamb"
re-secure headliner.
Re-install rear cargo light.
What I did,
Remove cargo light behind second row seat.
Remove D-pillar seatbelt on driverside and the plastic.
Remove caps holding up headliner and separate the headliner at the rear cargo hatch.
Remove grab handle and plastics from rear hatch.
Allow headliner to droop a little in order to run wire (2 separate 18G) to rear cargo light
Run wire from body to rear hatch utilizing rubber "conduit" already in place for rear defrost and wiper motor wiring.
Use vampire clips to attach new wire to existing wire for rear cargo light.
Cut hole in plastic shroud of rear hatch to mount cargo light to.
Use a small piece of wire run to the cargo light into the light and secure wire using a small round eyelet wire terminal.
Test light after ground wire attached to mounting bolt. (I used one of the bolts holding the wiper motor to the rear hatch)
secure light to plastic shroud.
Re-install shroud.
Re-secure rubber conduit to hatch and body opening inside the "door jamb"
re-secure headliner.
Re-install rear cargo light.