I just switched my tachometer/clock for one in better condition. I had new capacitors installed in the clock. Also installed a better used fuel/temp/oil gauge. Upon testing the gauges went awry. The hazard warning switch causes the fuel needle move left and right in rhythm with the ticking and the fuel gauge goes to full when the headlights are turned on. Am I attaching the muti-pin electrical harness incorrectly or might the soldering be bad on my replacement gauges? Your help would be most appreciated! 1985 300D.