After I posted yesterday, I found out some more and re-read some things.
So as mentioned (and I missed the first time) the place on the junction block for power is empty- thus why the writeup here just has you tap the brake switch. However, if you have the whole harness, there should be 2 posts open with the plug literally right next to where it "should" go in the junction block with the same plug.
I hooked the battery back up, and tested, and sure enough, one of those posts gets switched power- and it is the correct colored one too. In order to make the plug fit, though, you must shave off the tab on the plug.
There is a rather ingenious yet simple way that they made all of those plugs going into the junction block correctly. In addition to various bevels on corners of the plugs, there are tabs that are either on the top, middle, or bottom of one side thus making it very hard to plug into the wrong place.
In this instance, it doesn't matter as I'm installing a feature that was never there, but still, it's pretty cool. I've also found the same thing for the OBC as I'm trying to get the CODE feature to work there.