Alrighty then. I finally got my tach today in the mail. I know from reading several archive entries about the tach that it should be an easy job. The tach should just plug onto pins when I screw it into where the large clock went on the left side of the cluster, and I just plug the white/red wire into the connector on the back of the tach, right?

Problem is, the tach has FIVE connectors on the BACK of it, and the only wires hanging freely behind the dash are two red ones which terminate with a blue connector (dangling end) and the other end of these wires goes into some mechanically driven unit which creates an electrical signal. What the hell is this thing?

The 3 connectors at the top of the back of the tach are in this configuration |_| and they correspond to the pins which the tach slides into on the instrument cluster, so I don't think those connectors are necessary. The bottom two connector pins on the tach, however, are mysterious. I'm assuming they correspond to the 'signal' wire to tell the tach what to register, but where are these wires? Could it be possible that the two red wires coming from the electrical/mechanical unit connect to this? The plug at the end of the strange elec/mech device has small female bullet type connectors and the back of the tach has connectors like this || which means it definitely doesn't just 'plug in'.

So what do I do? Thanks to everybody for all of your help.