instrument upgrade

[redhot67]

I need help on upgrading the instrument panel on m 67 C10. It currently has the three-hole with idiot light setup, and I want to go to the full gauge panel with tach (no vac gauge). There seem to be plenty of aftermarket setups around but I am not clear about what wiring is required. They all say that the tach conversion stuff is included and a new circuit board, but I don’t know about the oil-amp-temp. Will I have to change the wiring harness, or will the new setup work by plugging in the existing harness?

Any thoughts on going with this setup versus a custom panel such as Dolphin gauges in a billet panel?

Any advice appreciated!