Hello: I'm trying to find a drawing of the Uno R3 board with dimensions for the mounting holes. Can't seem to get Eagle 6 to open the .brd or .sch files. Thanks!
They have opened for me in the past. Did you extract them from the zip file before opening them?
I think sparkfun library also has shield layouts with mounting holes.
You may find this helpful: http://www.adafruit.com/datasheets/arduino_hole_dimensions.pdf
Very helpful, thanks.