wire for speed signal '98 Ram

I am installing a kenwood navigation system in my truck. I have to hook up a speedo wire to the system. Where can i hook up this wire (tap into the speedo wire) i have tried to find this wire at the dash cluster but not sure about which one it is. None of the wires are color coded to the wire diagrams.......Any Ideas about where to tap into the speed signal??
thanks

Does anybody know about this???

If you want you can just go to the speed sensor wire at the tranny, its located on the drivers side about where you'd normally find a speedo cable it looks just like the cable gear on earlier trannies but with a wire coming out instead.