Help with neck rotation

Hello. I am extremely new to servos and controllers. I would like some assistance in getting neck movement in a Halloween prop I’m building. I want to control the turning of a neck approximately 90 degrees. The photo shows a 1"pvc cross with a 1/2" pvc running through it supported by bushings. What would the best way to mount a servo, vertically or horizontally? Would mount a screw in the 1/2 tube and then attach a linkage to it. Any assistance would be appreciated.