They have the paper barcode and some also have a metal ID tag like mine did.
Under the Tech Tips section here on the left bar regarding the T5 conversion an electric to mechanical box is mentioned. These guys sell one for $275 plus $50 for another needed part.
http://www.speedometerplus.com/speedometers____gauges__servic/speedometers____gauges__servic.htm The correct tail shaft and housing cost me $250 through the tranny shop.
