I want to install an auxiliary power port in the back of my van right behind the bulkhead. Anyone have a wiring diagram that will show me where i can tap into 12V hot and Ground?

 

If you are just adding a power port, then you could most likely go off the power under the driver's seat. You won't be drawing that much, and that main breaker is big. I would not connect anything large, like and audio amp to that, but a power port should be fine. Make sure you fuse whatever you add.
Alternatively, you could rob off the ports in the dash.....most people only use the 12v power ports for chargers anyway...
Ground to body/chassis, but clean the paint off, and use a bolt, nut and washer if you can rather than a screw.

 

which wire under the seat is the 12 V hot? Do you have a diagram or color code chart?

 

If you pull the cover off the panel under the drivers seat, you can see the bolt that has the main power wire that goes to it.

 

Awesome... Thank you!!!