Finding the accessory power lead on the VTX 1800

Preface
This is a walk-through for finding and using the accessory power lead on the VTX 1800. This lead does not exist on the VTX 1300 and some newer 1800 models don't have it either. If you need this lead but don't know if it exists on your bike I recommend spending a few minutes removing the seat and checking it out yourself.
This is a switched power source, which means that it goes on and off with the key on the bike. When you turn the key on this wire (and any accessory you attach to it) gets power, when you turn the key off it loses power. This wire comes straight from the battery and is fused with a 30A fuse, but it also runs most of the electronics on the bike (after the key) so don't put accessories on this lead that pull a lot of power or else you'll start blowing fuses. This wire would work well for accessories that have a low power draw or as a "trigger" for a relay for larger accessories. As with all mods, you do this at your own risk - I don't want anyone blaming me because they did this and blew up their bike. I also want to thank Todd from the VTXOA who helped inspire me to finally finish this write-up.

Preparation/supplies

6mm allen and 10mm socket (to remove your seat)

Assorted electrical tools, wire, connectors, etc - this will vary depending on the accessory you are adding

Process
Read this entire process in advance so you know what you're dealing with - if you understand this process and know what accessory you want to add in advance you can plan for the proper materials to make your connections. This helps prevent multiple trips to the auto store for wire or connectors you may not have laying around the garage.
Remove the seat from the bike, this usually entails a 10mm socket on the passenger seat nut and a 6mm allen on the front seat bolts. With the seat off slide this black cover back to find the wire harnesses inside:

Ignore the fact that I have the ECU unplugged in the pic, this is a pic from a bike in the garage I'm working on.
Now we'll get into that bundle and find this plug:

If you look at the plug you will see that one side (left side in this pic) has 4 wires coming into it and the other side (right side in this pic) only has 3 wires coming into it. This is where we're going to get our power from.
Separate the plug:

You can now see the plug on the left has 4 connectors to coincide with it's 4 wires and the right plug has 3 connectors for it's 3 wires. In the pic you can actually see the empty spot where there is no plug on the right.
If you can find a good "spade" type connector like the OEM ones you can actually put it into the stock plug and it will look like the bike came from the factory this way.
So that's pretty much it, now you know where there is a switched power source on your bike and how to hook into it, now you just need to find an accessory you want to use and wire it up.

Afterthoughts
There's not much to say here, this is just a bit of info about the bike to be used as you see fit.
I find that little details like this help the bike look nicer, rather than tying a wire directly to the battery - plus since this is a switched power source you don't have to worry about forgetting to turn the accessory off when you turn the bike off. This means no waking up to a dead battery and that is always a good thing.