Splicing into the reverse lights
It's a bad idea to have a large draw on the factory wiring... there's enough going on there already for what 16ga?? I don't recall, haven't messed with it in a while... Either way yeah an LED bar should be ok, but a set of fog, floods or offroads could start a meltdown...
Bar-B-Q
LEDs don't draw enough power to create a problem which is why this is ok. If you draw too much power from the wire like with the lights the OP wants to, you'll burn your truck to the ground from an electrical fire. You never want to pull that much current from a wire like that. To OP: Just wire in a relay, better safe than sorry. You probably think your truck is hot now, just wait until that wire overheats, better have the marshmallows and hotdogs ready.
I got a LED brake bar that had reverse lights integrated. The brake, left turn, and right turn all wired into the tow harness, but I had to tap into the reverse light to get the reverse on the led bar working. I just taped into it from the rear light and everything works fine no problem. Like other people said, a LED bar should be fine, anything else you would want a dedicated wire running to the battery with a fuse.
You got a link? I'll check it out in the morning. Right now my KC's just have wires running from them to a switch, then a wire from the battery to the switch, and a grounding wire.
Normally I would always run a Relay. However in my case I was using two small light bars, 5 LED's a piece. They draw almost nothing. So I spliced them directly into the reverse lights. It's been 4 months with no problems. However if it was anything other than LED, such as halogen, or even a large LED light bar such as the one I have on the front of my truck I would run a relay, no doubt. It's a little more work, but well worth it. You can even run a separate switch so that you can power the lights whenever you want. Such as hooking up a trailer, or someone tailgating.






