I have a 1991 Convertible RS 305 TBI. My Tach reads 6500 at idle and goes up from there, my guess is the sensor but I read somthing about another problem area in the Tach cuircut. Any help would be great. Also has anyone swaped the gauges in a 1990+ Camaro? I want a 140+ speedo but like the "round" dash that's in the car now. Dose anyone have the gauges that I need to do this? A 91/92 pasanger fender?