Answering it myself. Handlebars and covers, and associated parts must be removed. The steering yoke goes through a hole in the front fender from the bottom, so steering yoke/front forks must be removed to replace the fender. And there are cageless upper and lower steering bearings with a handful of balls each to deal with.
See pages 12-16 and 12-17 in the service manual for a couple pictures showing the fender attachment. No specific instructions on replacing the fender, but it shows the 3 bolts hold it to the top of the fork tube brace, and the steering yoke axis goes through the fender from the bottom. No easy replacement technique.
Icing on the crap cake? Kymco has discontinued the Wineberry/Dark Red color fender that I need to match the original. Black and silver are both available (as are several other non-complimentary colors), and I suppose either one would look OK against the otherwise wine-red color of the rest of the scoot.