The cruise control servo on these is right next to the battery, when equipped with it. Yours being a DX, it was probably an optional thing.
I have a little 125 Guzzi single that is about 60 years old laying in a basket, a friend gave it to me that did not want to work on it. I also have a little Capriolo 100cc bike that has a very interesting face-cam engine, another bike I have never rode or worked on that came from the widow of it's original owner. That is it for my Italian collection. My old man was a Matchless dealer/racer in the 50s and early 60s, and the distributor for the Matchless also sold the Ducati and Guzzi and Norton etc. bikes, so that is how I ended up riding Norton and other Brit bikes my entire life. The lucky people had Honda dealers for fathers. When I was a kid we had a little Gilera I used to ride through the woods all the time, it is still sitting in my father's barn. If I live to be about 200 years old I might even get all mine and my father's old bikes running again. Don't hold your breath for that........Nortonguy, I was a member of the San Diego Norton club many years ago although I only had an assortment of Italian bikes then. Now I just have several