The good news: I guessed that Velo Orange 650b 52mm fenders would clear Panaracer GravelKing smooth 42mm tires, so I ordered a set and it worked out fine. After the usual struggles trying to get achieve a good fender line over the rear tire, I stumbled onto the right height of cork spacers and fender stay length (the hacksaw got a workout, a few millimeters at a time) to get a decent installation.
We put the bike up in a stationary trainer Saturday morning and tweaked the saddle and handlebar locations for us both, aired up the tires, and went out to Hains Point, our local bike loop in southwest D.C.
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