ARCH DELUXE

On their upcoming kitsch-rich PopMart tour, U2 will celebrate the cheesing of America -- and maybe even Mayor McCheese. Among the props on the 62-city tour, which kicks off in Las Vegas April 25, is a 100-foot-high arch that straddles the stage (it also appears on the back cover of Pop). Band manager PAUL MCGUINNESS doesn't see any similarity between U2's arch and Mickey D's -- even though the press kit describes it as a ''golden arch.'' ''McDonald's? Never thought of that,'' says McGuinness, perhaps coyly. ''I think it looks a lot like the arch in St. Louis.'' Even Ronald McDonald is in the dark about the arch. ''Honestly, it's the first that we've heard of it,'' says McDonald's spokeswoman Julie Cleary. And judging from her reaction, it seems unlikely the fast-food chain will take legal action against the Irish band. ''It certainly sounds like it's all in good fun,'' adds Cleary. As another famed burger meister would say: Have it your way.