Detailed instructions should be in the airplanes soon. The pump is located just South of the taxiway that goes into the Birdcage. The taxi lane shown below runs just next to the "road" for airport vehicles. Use the taxi lane, not the "road". Just tell ground control that you want to taxi to USA Jet fuel pumps.
At this point in time we do not yet have a MANG account with USA Jet, so use your credit card and turn in the receipt with your MANG bill for reimbursement.

The operation is similar to that of AvFlight:
1. Ground the aircraft with
the ground clip.
2. Place drain mats over ramp
drains in case of a spill (this is new).
3. Insert credit card and
follow instructions on the display. Do not use
the "Fill-up" key, but select some fixed amount of fuel
that is more than you need. Then you will only be charged for
what you actually dispense. But the "Fill-up" key
temporarily charges you for a higher amount and then refunds the
difference to your card several days later.
4. Rotate "swing
arm" on side of pump to the "ON" position and dispense fuel.
5. Replace nozzle and rotate
"swing arm" to the "OFF" position. Stow
drain mats back into the orange bin.
6. Pick up your receipt from
the control panel.
These instructions have been abbreviated. See the complete instructions in the airplanes.
Here are some more pictures. The one below shows more detail of the pump:

Here is the control panel where you put your credit card, enter the number of gallons (maximum) to dispense, and pick up your receipt:

Here is how the mats cover the ramp drains:
