got the wheel off and replaced today. just needed a little coaxing with, as mentioned, upward pressure and a hammer. the nut was stripped, but the shaft was still threaded ok, so i just got a new nut and slipped the new ss/teak center wheel on. looks soooo much better.
also put a couple flush rod holders in the gunnels and rewired and installed new bow and stern night lights. she's getting there.