Plot clock arm for servo horn

Doing a printed version of http://www.thingiverse.com/thing:248009/ i realized the servoarms are harder to mount than i thought.
Therefore, using the arms from http://www.thingiverse.com/thing:250204 and the servohorn http://www.thingiverse.com/thing:42796 added a servohornsized cutout.
A 9g servohorn fits into the hole and can be mounted using two screws.