You could also go into Tools->Settings->Advanced and set the Achive/Restore folder to be on the other drive. Then use the File->Archive Application function to archive the game to that folder. Then go to Tools->Settings->General-> and check the Prompt To Enter Installation Directory. Now do a File->Restore Archive and point it to the new archive you made on the second drive. Then you can install it whereever you like.
Once that is all done, you can delete the version on the Main Drive and then delete the archive on the second drive.
That will also get the game moved for you.