W6pea,my truck is a 2015 MY,this trucks body harness was not coded with a build for Bed Cargo lamps and was not available for 2015. Your truck is a 2016 this MY was coded to build with a option for Bed Cargo lamps.If you order for example the Luxury Grp (LP2) this includes bed lamps, I believe this is the reason you are stating look under your bed you will see a connector for in 2016 a Tradesman or a SLT will have that connector available for power since it is wired from the Power control Module to the BCM. A truck either a dealer ordered,or customer ordered has a V.I.N specfic harness ordered by sales codes like LPL for example. This allows RAM not to waste money on excessive harness builds,like wiring and connectors and relays etc..etc imagine the cost over 450,000 trucks a year. What I am trying to do is wire throught the Headlamp control module or through the CabHigh brake/lamp wiring.The cargo bed lamps have to be activated through that curcuit or they would come on with the door opening or the interior light switch etc...If you notice what Sag2 posted is a V.I.N. ordered RAM with RamBox's notice as well the C-1 pin 5 connection as well in the curcuit,it only drives the cab high mounted light lens,does not show additional wiring terminating at a plug for a plug and play option..Interesting through the tech was surprised that the LPL code was available to upload,but when uploaded in to the truck's PCM after sleeping for several days the lights never woke up to be powered.Then it dawn on me possibly the BCM circuit board at the C-1 location pin 5 is even routed for power,there is a slot through,but then again their are 3 slots open at that C-1 connector...