Turns out that my fork was the right size after all...looks like the problem was that the mounts for the front brakes were welded on in the position that they would be if it had been a 26" fork (i.e., they were in the correct position if you measured from the bottom up for a 26" fork). I've never heard of a defect like this with Surly's products, but I'm not surprised that it has happened to me (dumb luck).

Anyway, they're sending a new fork and it should be here today so hopefully I'll be able to be riding the LHT this weekend. My only concern now is that they're going to send the wrong color and I'll be stuck with a strange combo. I so want to simply ride this bike, it's killing me.