Tach amps are available, and necessary to use your Veglia with a modern ignition (that may only output 12v). Here is much cheaper... https://www.ebay.com/itm/142171581596
Or, you could be crazy like me and retrofit a modern stepper tach into a Veglia can... https://pantera.infopop.cc/top...93#19905352128593293
...geez, I had a lot more time on my hands then...and as predicted, it sits on the shelf and another in the car...