HELP!?!? powering both arduino uno and adafruit motor shield!!

Hello I'm working on a rc car and have it ready to go mostly besides for one problem. I don't know how to power the arduino and the motor shield. I have 6v needed into the 5-12 volts port on the adafruit but that won't also feed into the arduino uno which is below the adafruit motor shield. I want to be able to power both the uno and the shield but I don't want to use a usb port for the uno to power since my car will be moving around.

How can I power both my arduino uno and the adafruit motor shield without a usb? I already have the adafruit powered perfectly with the 5-12 volt port on the shield but I cannot get that to feed into the uno since it does not have ports below for it on UNO. PLEASE HELP!!

I have the adafruit motor shield. I remember the shield had a jumper to allow connection to Arduino's Vin pin. If you connect that jumper, then the shield will supply the Arduino.

Have you tried asking for support for the Adafruit product at the Adafruit forum?