I take it by your wording you are not in the US or Canada
1) Check with your dealer in Country, in Canada, depending on year, the wiring harness has
the provision for a tachometer (rev counter).
2) If the harness has provision for a Tachometer you simply need to get one of the correct
year from your local auto recycler and install it. (Easy)
3) If it does not have provision for the factory Tach, I would follow Blasted's advice, it's the
easiest-simplest-cheapest route to go.
Zag