I have a '82 CJ8 with the 4 cylinder 2.5L Iron Duke. It did not come with the factory tachometer, but I have one from a donor dash. I am guessing the tachometer is from the 258 or 304. Is there a way to make this tachometer work correctly with the iron duke? Also, would the wiring harness already have the connections for the factory tach? Any help is appreciated.