by Alan » Sun Nov 21, 2010 11:09 am
There is a post on this forum that will walk you through the process of installing the tach cluster in the dash. It is pretty straight forward. It will show you how to wire the tach to work if your wiring harness doesn't have the wire already. I'm not sure if the 89 model had the wiring in place or not. My 91 model did have the wiring in place. You will need the oil sending unit for a gauge instead of a light for the oil pressure gauge to work. If the truck your getting the cluster from has the engine in it, go ahead and get the oil sending unit off the engine. It is located right next to the oil filter. It has one wire running to it.