Got the crane pivot servo working. Not completely satisfied with the pinion to servo attachment. I am afraid it won't be long before the threaded bolt comes loose in the top gear of the servo. I did have a nut on the top of it but didn't have enough clearance for the pinion above the truck body, so I had to remove the locking nut. Also the pinion does not fit on the thread of the 4-40 perfectly, so the pinion is not perfectly true and wobbles just a tiny bit.
http://youtu.be/_4BFGXFBoYg
Jim