If I were you (and this is what I plan to do, just because I am a wannabe redneck) I would buy the biggest tachometer you can find, preferably with a shift light, and stick it in your window. I have the same cluster as you do NOW. I originally tried to swap a full cluster in and that peice didnt work at all. When I swapped to the current one (the same one you have) everything worked. the full cluster that didnt work came of off (what I believe) a 2.8.... it didnt seem to want to work with my 4.0. My gas was always WAY WAY more than full, though occasionally it read correct, and neither my oil or temp gauges worked. They just sat in the Key off position. Anyway, if that helps, then great!