90 to 94 silverado 4x4 cluster swap?

I have 1990 silverado that has the plain nothing cluster. my friend has a 94 that is identical looking except he has the cluster with the lit needles and a tac. someone told me that you could just but a 94-95 cluster and it should plug in but the 94 has a presure ribbon plug and my 90 has a pin plug, does anyone have a detailed wireing diagram for a 90 and 94/95. I have the plugs for both and already have a 94/95 clutser with the tac. I would like to convert to the newer style?
thanks for any help.
Chris