66 tranny problems

[66redw/white]

so heres the problem fellas. i think i may have it figured out but id like to run it by the gurus before i go spendin to much money. truck has an inline 6 and a 3 speed. was runnin and drivin great. well then the clutch pedal got real stiff and the tranny wont go into ANY gears. to get home i had to start the truck in gear with no clutch and then ghost shift the rest of the way home. so i was thinkin maybe the throwout bearing. got home and got under the truck and had my wife hit the clutch a few times. i can see it moving back and forth like it should. so im thinkin maybe the diaphrams on the presure plate are shot? is this makin any sense to yall? help would be greatly apreciated.