Charles Lamb;
If by "automotive" you mean analog (round face with a dial and pointer), then yes you can. But just any old tach will not work. Your best bet will be ordering the Kirk Engines Tach found on the sponsor link above. But the Equus brand tachs will work also.
You see most tachs correct for the number of cylinders inside the circuit in the tach, which is why if you order an Autometer tach and use it on a 4 or 6 cyl you have to cut the little wires to make it have the proper resistance for the signal. Kirk has their's preset with the proper guts to work on a kohler. Even the Autometer Jr. Dragster tach won't work because it is setup for B&S ignition, not a points style.
The Equus Gauge is way ahead of the game right now. It comes with a pickup wire to wrap around a plug or coil wire to sense the spark signal or a direct signal wire to plug right into an aftermarket ignition like a MSD. It also can be quickly switched between 1to 8 cylinder with a push of a button and will also work on a DIS system.
It baffles me why such an industry leader like Autometer doesn't make a product so versatile. But if they don't need the business, I'll be happy to go elsewhere...
Again check out the Kirk Tach it WILL work, if you want something more "in your face" check out the Equus. And that you can see and get at O'Riley's