The jumping shown in the second video could be electrical noise. Automotive electrical supply is notoriously noisy. Be sure all the contacts on the plug are well seated and that you have a good electrical ground connection.
The tachometer in the fist video does look a little like a sticking needle or something in its drive motor. As for the temperature and fuel gauges, I would verify proper working of both gauges. It seems unlikely that the sensors could be damaged by what you have done. I had a problem last year with the temperature gauge on a tractor -- it read normally on start-up, but quickly went into the red. Was able to remove just that part of the cluster, test it with hot water and eventually found that the problem was a loose needle. That is, the gauge mechanism was designed so the spindle went considerably below "cold" at rest. The loose needle was forced 10 to 15° CW on the shaft by the physical stop at "cold." Thus, at cold, it was still against the CCW stop, but as soon as it warmed a little, it was way past operating temp. Your needle could be set so far off that it never moves into warm.
John