Here are some pictures for the electrical and vacuum locations:
This is the left hand side storage - open this and you can see the main power line
You can see the area where there is a hole in the bulkhead - the lower most black wire is the power from the plug area heading over to the right side of the rig
On the right side the Vacuum is below this panel as in the second picture.
Behind this panel that is screwed on is area where all the wires go into the main electrical panel and the charger/converter is behind this panel as well. Probably the best place to splice in the unit.