Guruplug Server Plus U-SNAP\GPIO mapping pinout information.
With the Guruplug Server Plus standing on end (and the logo text the correct way up) pin 1
is nearest the bottom (making pin 10 nearest the top, the opposite of the listing below).

pin GPIO#
1 39
2 43
3 40
4 41
5 42
6 - RESET
7 - 3v3
8 - GND
9 - NC
10 38