Don't forget you should be Able to have a seperate independent locations folder that both installs point to and share, saves doubling up on tracks in both installs. Worked for rFactor so I'm guessing the same will apply for this sim
EDIT: but that would be no good if track data info gets tweaked etc by the sync tool. And now I'm thinking about it, GSC sync will probably keep wanting to put the tracks back into the install being sync 'd... Oh well was a thought