Cone Assassin

well here's my issue I bought a race prepped '93 civic and the previous owner tore out the whole interior even the dash and gauges...:L. so now I'm struggling with wiring. I found a gauge cluster and wired it into the fuse panel with the proper wiring connectors, but it does nothing. I have no issue with hooking up lights and blinkers to custom switches, the problem lies with the speedo. I want to remove the speedo from the cluster and wire it directly to the speed sensor and I don't know what wires do what and I'm not making much sense of all my wiring charts I have 3 wires coming off the sensor and positive negitive and (sp) on the back of the speedo gauge.

this is the only thing that is stopping me from a safety for my car and could really use the help

thanks