here is a link to an animation of how the epic works:
http://www.zdspb.com/media/tech/animations/epic.gif
much of the valve componets are housed inside the trigger frame. if you could mod the foregrip from an invert mini to mount of the front of the epic and have that house the battery and board, you might be able to fit a switch behind the trigger and a solenoid in the grip. i haven't seen one up close to know if there is enough room in the frame to do this, but i would love to get my hands on one and find out.