I may have to call the Dakota guys on that one, what I'm getting form the website is that each cable adaptor is manufactured for a specific speedometer made by themselves. But, I have solved the costly speedo issue - Street Bike / Motorcycle Speedometers - Aftermarket Speedometer Upgrades - ElectroSport Industries.
I have an Acewell on my Yamaha Cafe. It works pretty well, but for the vintage Yammie at least I couldn't wire certain things like oil light due to reversed polarity of those circuits. I would get the manual first and study both it and your wiring diagram before you drop the cash on it.
Thats a good call Hawk. Im actually considering chopping my front fairing stay that holds speedo/oil cooler/headlight so that only supports the oil cooler. That way, I can fork mount my dual 4" headlights and my new speedo. If I went the oil cooler relocation route it may not look right since im chopping my left and right side fairing, similar to picture below. Copy and paste cant get the pic to work. - http://w1.bikepics.com/pics/2003/09/02/bikepics-64620-full.jpg
^ Just thought I would mention that I have the same headlight fairing for sale as pictured on the streetfighter above for $20 with the lights. I have a set of fork brackets for another$10 which is all you need to mount up. I have a post up with the parts for sale. My '83 "streetfighter" is also pictured in the same post and the same fairing is on my xs400 project. Check it out here --> http://vfrworld.com/forums/1st-2nd-generation-1983-1989/31050-vf750f-parts-sale-couple-needed.html