I want to either overhaul or replace the (threaded) headset on an old Schwinn I picked up, but I can't figure out how I'm supposed to get it off. Whereas the Park Tool website suggests that there should be two hex thingies for me to turn relative to each other, I only see one (it turns with the fork). I tried holding the fork, but that didn't get anywhere without me worrying that I'd damage something. Any help would be appreciated.
large headset picture: http://web.mit.edu/~xsdg/Public/pict...sc_9922.bf.jpg
the bike: http://web.mit.edu/~xsdg/Public/pict...9929.small.jpg