Another part that won't work

Why is that everytime something goes wrong with my XJ it's always on a weekend when the dealers and junkyards are closed? Was going to pick up some things from TPI MJ and got 16.7 miles down the road and the speedometer stopped working. When I got home I took it out and found that the coating was melted and the cable itself broke. Went to see if the parts store had them and they claimed they did but they had some other style and argued with me that this was the one I need and I quickly went out and got the old one and asked the "Mr. Know-it-all"........does this look like that? Guess I better not go back there for a while. He wasn't happy with me. So if anyone might have one I posted in the wanted section.