Trailer lights hook up
 

I know its been beat to death, but I used my old friend the search feature and came up with nothing.
I'm installing a Curt 55190 trailer isolator. The Rave electric circuit diagrams do not adequately describe the actual trailer socket on the Disco before the accessory is installed. I have 9 wires going to the plug designed to accept the fancy trailer hook up. Rave only lists 7. I've figured out which one is "hot" with key on to power the isolator transformer, but my question is: should I splice both left and right tail light hots to my single taillight input on the isolator? Or just use one or the other?
Thanks in advance to anyone who has already done this.

Ended up splicing both left and right into trailer hook up. I reasoned that lack of taillights on truck (left or right) will tell me which fuse (11 or 33 on passenger compartment box.) But if one blows while trailering, I should still have both tail lights on trailer. Everything works perfect.

Nice work.