Pixhawk/Arduino Mega box

A simple box based on the excellent Ultimate Box Maker by Heartman, this is a box that holds an Arduino Mega, a Pixhawk, the RadioLink GPS and a 4-line display. Holes for USB for both boards. Mount the Pixhawk on a block of foam to bring it to the right height for the USB hole. The display is from SainSmart. There are guides in the top for the GPS and the bottom for the Pixhawk to keep them perfectly aligned. I have an RC receiver Velcro'd to the inside of the top. Wedge the buzzer between the