Bought a second set of wheels for my Surly 1x1 Rat Ride and installed them today. The stock wheels consists of Surly hubs and 24-inch Large Marge rims to which I've mounted absurdly heavy Arrow Wide Bite tires. The new wheels are 26-inch WTB XCs outfitted with Exiwolf tires. Everything lines up perfectly, so I can switch the wheelsets with minimal fiddling.
In the process of installing the new wheels, I came up with an easy method for holding the rear wheel in place while I tighten the axle nuts: I stuffed a loosely folded tube between the bottom bracket and the rear tire and inflated it to bulging. The tube pushed the axle back in the trackends while clamping the rim evenly between the stays. When I judged that the chain was sufficiently taut, I stopped pumping, tightened the nuts, then deflated the tube. Easy.