idiot light conversion

I have an 86 el camino with the stock idiot lights and tach. these have to go! I want to swap in a gauge and tach cluster from a monte ss, but have no idea whats involved as far as wiring is concerned. i've found clusters that come with the "all important plug for conversion", meanwhile the seller actualy knows nothing about it. :wtf: DOES ANYBODY KNOW?!?!?! any help would be greatly appreciated.
:ylsuper:

I swapped in an 84 Monte cluster into my 80 Elcamino. Had to rewire the cluster plug. If it comes with the plug that will make it easier. But I would recommend finding the cluster wiring diagram. The wires are in different locations for the lights and the gauges.