This is a coin cache so you can only trade coins in it. The coordinates above are not the right ones but the cache is on that side of the motorway.
A:9
B:5
C:0
D:5
E:4
F:8
G:1
H:2
I:2
J:3
K:6
L:5
M:0
N:3
O:9
P:2
Q:4
R:7
S:2
T:7
U:8
V:8
W:9
X:2
Y:3
Z:6
Update 2014-11-16: There have been a few comments that the coordinates are a bit off. When I replaced the box today I checked the coordinates and my GPS said that ground zero was 4 meters away when I was at the hiding spot. I think that is within the normal error margin, but if you want updated coordinates you should subtract 2 from the N coordinate and 2 from the E coordinate you get from the puzzle.