This cache is not at the published co-ordinates but it is a round about here but NOT on the round about which is a round about way of saying keep clear of the busy roads.
To find GZ you'll need to work out the next number in the following sequence (represented by letters ) and then do a little simple arithmetic.
1
11
21
1211
111221
312211
13112221
1113213211
ABCDEFGHIJKLMN
Then the cache is located at :
S 23 08.A+N , J+D-K , C+H-N
E 150 44. L+M , F+M+D , D+A-F
Have fun on your search.
Check Sum :A+B+C+D+E+F+G+H+I+J+K+L+M+N = 23