The Curt taillight converter, part # C55355 is designed to intercept the signals going to the taillight assemblies by plugging inline with the connection shown at the :35 second mark in the video I've linked you to.
I spoke with my contact at Curt, who tells me that on vehicles that were equipped with the compressor, the connectors you're looking for could be closer to the door jamb or in front of the compressor, closer toward the front of the vehicle. You might need to pull the trim... view full answer...
When installing the Curt wiring harness, # C55355, on a 2001 Oldsmobile Silhouette, the 4-Way is meant to be stowed inside the rear cargo area and pulled out when in use. The hatch door can be closed on the wiring and the weather stripping will protect it. Take a look at the video I have linked as an example.
If you wanted to route it through the bottom of the van interior and to the bottom, you may be able to find a grommet at the very bottom of the cargo area through which you can route... view full answer...