Not so much an urban legend...
But back in early 1980s Wolverhampton, at the height of Dallas-fever, there was the thrilling TV climax to "who shot JR." While waiting for the summer months of white dog turds and playing in the hollow tree on Upper Green (in the posh bit of Wolverhampton) to fade and for the answer to be revealed, we would get the occasional Mivvy or Cider Barrel from Mr. Boselli, the local ice cream man who had the Upper Green patch for his ice cream van.

But all is not so idyllic in the world of ice cream vans. An interloper parked his ice cream van in Mr. Boselli's spot leading to an almighty row betwixt the two of them. It ended badly for the interloper as Mr. Boselli returned to his home to fetch his shotgun before gunning down his soft-serve rival with both barrels at close range.

That led to the widely seen graffiti, "Boselli shot JR." I passed that every day on the way to school for the next 6 years.
(Gusofnavarone always makes a map of france from sarnies, Mon 9 Jan 2017, 16:50, Reply)