changing gauge cluster in 78 Chev

[rocktriviagod]

My 'new ' 78 Chev stepside currently has gauge cluster with big speedo and gas gauge and four idiot lights. I bought a different cluster on ebay (from a 73 Suburban) That has all four gauges on the left with the big speedo and Factory tach. How many different sending units and what-not will I have to purchase to make this switch? Will the wiring for the idiot lights hook directly to the new gauges or do I need more 'stuff' to get them all hooked up? Any help, or links to other web sites woulbd be appreciated.
Craig