Clockwise. The early version of the mech had pot metal race riveted in place. As the windshild gasket wore out, the owner would tighten the crank harder. Eventually breaking the last teeth off. The later version had stamped steel teeth. As said, spray penetrating oil on the gears and the arm pivots. Cam you get to it from under the dash and help the mech to turn? In the pickup the dash comes off so you can get to the mech. Don't force it. A guy in Ohio make a nice replacement gear race.