What Sort of Clutch Problem

[ebrown@ms.com]

     When cold and at a standstill, putting my '57 Plus 4 (#3714) into gear 
     is easy, noiseless, no grinding. Increasingly, after a good warm up, 
     it is hard (again, at a standstill) to get the car into reverse or 
     first without grinding the gears. Once moving, is not a problem with 
     the remaining three gears. There's no free play to speak of in the 
     clutch mechanism, and the clutch otherwise seems fine, no juddering or 
     slipping. I wonder if any of you have any thoughts? I am keeping my 
     fingers crossed about doing a midsummer clutch rebuild....
     
     Regards to all-
     
     Chip Brown