I posted this speedometer query as part of another post dealing with "door panels", but decided to post one exclusive to the same '75 having a speedometer anomaly. It has a noticeable speedometer needle quiver, for the lack of a better term, when driving down the road. I had a video taken and sent to me when it was being field tested. It just seems to vibrate a little instead of holding steady. This is a new wiring harness, new cable, new instrument panel head. Is this quiver normal? I would suspect the cable, but it's brand new along with everything else.