Switching tach cluster for std. cluster?

[1968 Pontiac]

My daughter just bought a 95 GA SE with 4 cylinder. The speedo and odometer don't work. I'm going to change her instrument cluster which does not have the tach, but I'm wondering if I can just pop in a tachometer cluster from a 4 cylinder car without having to do any extra wiring? I don't have a manual yet for this car, is there an easy way to get to the instrument panel? My Mitchell book says the job takes about an hour IIRC. Thanks.

[xeroinfinity]

Im not sure if thiers a wire already ran for the tach or what color it would be.
If not it wouldnt be to difficult to run a wire from the ICM.

I'll check a wire diagram.

[skibum1111]

Dash harness is different. If you are pulling a cluster from a wreck, grab the entire dash harness at the same time. It's a bit of work to do it, and don't forget to change the oil pressure switch with a sending unit for a pressure gauge.

[1968 Pontiac]

Thanks. Does the dash harness only go to the firewall, or does it also go to the computer? I've pulled harnesses before, but that was on old pre-computer cars so it was relatively easy.

[skibum1111]

I do believe it connects on both sides of the dash. Should use the same ecm, just make sure it comes out of the same car ie same motor, transmission etc.