You're talking about their digital units...correct? To feed the speedo you would need an I/S pickup which operates off an elec. impulse. I believe most of the Dakota Digital units can be calibrated on the fly after they're installed. If not, then most likely you would need an item called a Speedo Healer to correct the output of the speedo pickup to give proper readings on the speedo. It's real easy to set, but you have to run the output from the pickup to the Speedo Healer unit(I installed a couple and laid them on the batt. cover), and from there forward to the speedo. As for the tach, usually just a wire to a 12v source, one to ground, and one to a yellow wire on one of the coils.
On the link, at the left you'll see Speedo Healer at the top. Click on it and read up. It's extremely effective, will make a +9,999% correction, and the "-" (negative correction if needed) is almost as big a spread. With that wide a correction available, it will work on nearly 100% of the installations. You just come up with a speed figure the bike is showing, and know what it should show, go to the website and enter the numbers and it tells you the setting to make. I always set it to show about 2-3 mph high so the ride has a small cushion, especially important in town. Like I said....don't think you need it with the Dakota Digital product though.
http://www.healtech-electronics.com/
