Hi guys,
You might find this site useful if trying to set your wedge up using the inbuilt compass. Its a simple calculator to measure your magnetic declination. Helps to work out how far away from magnetic south you need to aim your wedge/GEM to be pointing near the SCP. I found it useful for a quick roughout alingment. Eg My position calls for me to aim the tripod/wedge assembly 12 degrees east of magnetic south.
http://www.ngdc.noaa.gov/seg/geomag/jsp/Declination.jsp
Have fun
Paul