Hi John,
Usually they only seize when left for very long period of time. I am pretty suprised that it has seized after only a few weeks then again after 3 days!!
On the ones I have done, I have always replaced the clutch kit. Sometimes the flywheel has been corroded very badly and needed surface grinding but I doubt yours will need it if it's only been stood for a few weeks.
I used to work on a lot of Ministry of Defence vehicles and because they got stood for so long (esspecially the older vehicles) they used to seize a fair bit. Usually they were the worst to do and needed the clutch chiseling from the flywheel.