Here is a generic information packet from the GM Heritage Center archives. It will tell you everything there is to know (...almost...) about 1980 model year Chevy pickups.
http://www.gmheritagecenter.com/docs...olet-Truck.pdf
Depending on how interested you are in learning more about your specific truck, you can also send them $50 and your VIN and they will send you the original invoice for your specific truck (which includes all RPO content and pricing information).
Link is here:
http://www.gmmediaarchive.com/?page=3
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