Yea, it is only two wires that need to be moved. I know it was the black wire and the red wire, but I can't specifically remember where the pins needed to be moved. If you find a 90+ Mustang, just cut out the hard shell connector so you have the wire layout, and move the pins in your connector accordingly. That is what I did when I put a 93 multifunction switch in my 88. Personally, I like it better. It sticks out a little further and seems to be located a little closer to the steeringwheel.
Before you replace the switch, you might want to look at the hardshell connector first. The little clips that hold the terminal ends in the connector tend to get brittle and break, allowing the wire to slide out and not make good contact. I would pull the switch off and see if any of the wires have come loose first.