You now have plenty of good information to fabricate your own panel to replicate / improve on the original. Just follow the information provided to date, the infornation that will be provided with the tacho, the wiring diagrams and build your own, I suggest use new relays , switches and incapsulted LEDs with integral resistors.
However i notice you also ask about gauges for oil / water
. The existing wiring posted by Skipperpete shows on / off switching at the engine for these and you can use those for leds and buzzer as per original. (TEST them out of the engine since you are this far in)
If you want actual guages for water
temp and oil pressure then you can do that by buying
complete matched gauge and sender kits from your prefered online soucre. You may need to visit an automotive or hydrualic shop to obtain engine block to sender thread adapters. Then use the existing wiring from the new sender to tbe new gauge.
Note there are multiple discussions on this forum on lights and buzzers vs gauges, so I'm leaving that well alone, but just trying to close out your original query.