Viridian is right, but the access to the set-screw adjustment is hidden unless you know where to look. Look at the outer rim of the MMT's mounting base, about 30 degrees counter-clockwise from the cue device indentation -- you'll find an unmarked HOLE. The adjustment can be accessed by an Allen (5/64, I think) wrench. Caution, the arm will drop as soon as you loosen the set-screw.
Best of luck,
Joe
Best of luck,
Joe