Get something like this:

http://www3.towerhobbies.com/cgi-bin...&I=LXHUY9&P=SM

Pull or cut the red lead to the Rx to disable the BEC power input, match connectors to the motor, add a battery and you're there. I usually swap over to the red JST connectors for the motor side. Check the specs, some of these GWS ESC's have proper lipo cutoff voltages so you can go with a 7.4v 2S pack.

That's the setup I use with old fuel pumps. Easy and inexpensive.