Removing timing belt from cam pulley only. Possible?

[eyvind.spangen@c2i.net (Eyvind Spangen)]

how do Iremove the timing belt from the cam pulley only? I have to
change the head gasket, but the timing belt was new 20K miles ago, and
it sure looks like a hell of a job to change it, with removing old,
stuck pulleys etc.. so I thought I'll just take it off the cam pulley
and put in on again afterwards. But how do I loosen it enough to get
it off the pulley without removing the crank pulley? Isn't it a
tensioner thing at the water pump, that could be loosened? The car has
been standing for half a year outside, so everything is even more
stuck than it would have been on a 180K miles car...

ES