Just finished installing new gauge cluster, Speedo, Tic Toc Tac, Fuel, Temp and Oil on my 70 Roadrunner 383. Also installed new circuit board, light bulbs and low voltage limiter. All seemed to be fine at startup. Good oil pressure, fuel gauge reading well and temp gauge working fine. Until I started driving bout 5 miles. Then.... in perfect unison the fuel, temp and oil pressure gauges started moving to the left ever so slowly until they "zeroed" out. Then they started to reverse course, again very slowly then back to zero again. Always in complete unison. Any suggestions would be helpful. Ground issue? Low voltage limiter? Power issues at the gauge pin connector? Thanks.