Not sure on the tach problem, but when I recently put the gauge dash back in my 68 stepside, it wasn't grounded well, and when I turned the lights on, hit the brakes, turned on the signals, etc, the temp and fuel gauges would go nuts. I installed a ground on the back of the cluster, to the dash, and haven't had any problems since.
TJ
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68 C10 Short Step (Christine), 406 SB, TH350, 3.73's, currently going on the back burner.
New to my fleet,
67 C10 Panel (1 of 3827) (Nicknamed the laggin wagon, thanks to Josh, the webmaster), 292, p/s, speed, 86,000 orig. miles
Gridley, IL
bigbad406@msn.com
I'm on MSN messenger under that address if you would like to add me......
Also on AOL IM under the nick tommy85z
My Personal Homepage
The 67-72 gallery on MSN, feel free to submit your pics!
A pass-time of mine is storm spotting, click here to see Gridley IL's Emergency Services Homepage.
AOL SN- Tommy85z