I just set my Jeep Wrangler Unlimited w/ Blue Ox Base Plate / Tow Bars and RoadMaster's Invisibrake. 100% self-installation, takes a bit of time, but well worth the satisfaction of knowing it's done right and well.
I also used Hopkins plug-and-play trailer harness to keep from cutting into and splicing into factory wire, that if not done correctly could cause problems down the road. The only splice I had to make was an in-line splice to the brake switch indicator (12V) line indicating the brake has been depressed.
I didn't use the Invisibrake patch cable though, I tied the road master LED indicator light and buzzer into the 7-blade harness that came from the factory on the E450. Found the harness right behind the coin holder, just where one of these forums said it would be. On the Jeep side I used a six-pin round and wired the Jeep's brake switch indicator 12V signal on the Auxiliary output (Center Pin).
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