i have a 1980 datsun 720 which had been sitting about a year before i bought it. when i got the truck the clutch worked fine. a few days ago i went out to the truck and found the clutch pedal impossible to push down. i think there is something blocking the hydraulic line or something has slipped out of place... any suggestions on what to do?

well... start with the easiest things first... bleed the system and see if that works... check all the main pieces of it and see if anything seems broken or caught on something... if not then its somewhere in the clutch assembly