instrument Cluster Swap

have an 85 Caprice and i hate that it doesnt have the trip odometer, or gauges.

i found an 87-89 in a jy with the gauge cluster and wonder if they will just swap out or is the wiring different?

old one
http://i142.photobucket.com/albums/r...caprice003.jpg

What i want to use
http://paloneva.freeshell.org/caprice/caprice22.jpg