Easily. It SHOULD even be wired for one. Just gotta get a tach head and a sending unit. Sending unit is part E5TZ-17B384-A
I purchased mine from:
http://www.trademotion.com/parts/in...TZ-17B384-A&action=oePartSearch&siteid=214072
Tach head is a different story, you're gonna have to trawl the yards for one, or find one from another member. I do not know the part number, but they're easy to ID. There are two tachs, a 6000RPM (gasser) and a 4500RPM (ours), just read the numbers. Ours also have a warning red and orange (white on some) bar starting around 3500RPM.
They are rare to find in yards, at least the one near me, and I have lots of our trucks come through. Just pull the cluster, take off the four connection nuts, and it will pop right out. Oh and take the lens off of the instrument cluster. I recondition speedos from our trucks as a hobby, it's really easy if you just look at what you're taking off of the cluster. Anyhow. I BELIEVE the harness is in all of our trucks. Look for a four-wire connectour over on the passenger's fender. Two wires will go to the alternator harness (these are the wires for the ammeter), and the other two, I believe one is green with a yellow hash, should go to another connector, which in your case would be disconnected. Said connectour should be near the injectour pump gear cover. The sensour will just plug right in. There MAY OR MAY NOT be a big port in your gear cover, it will be pointed up about 45 degrees on the driver's side of the cover, the tach sensour will screw right into this port. If you don't have one, get one from a yard truck, they're easy to find, and I'm sure somebody on here has one you can purchase for a song.
That's about it, see this site for some pics of the sensour and where it goes:
http://www.dieselhub.com/maintenance/idi-tach-sensor.html
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