Install a Factory Tach Cluster??

[Ziptar]

I bought a Factory tach Cluster on ebay .

Assuming it works... Are the installs pretty straight forward as in Plug in?? I know I'll have to make a tach circuit and, since I have a diesel I'll have to pull it from the VSS on the back of the alternator.

As far as the rest of the wiring is it just a straight plug in?? or will I need to re-pin the connector? The current cluster has gauges now and not idiot lights, it has an 85MPH Speedo and the gas gauge is where the tack is on the one I bought.

Anyone done this swap can give me some tips? Anyone know where I can find a wiring diagram for pulling Tach from the Alternator?

Thanks,