Isuzu Repair: Clutch will not engage, clutch cylinder, clutch pedal

Question
My father and I have replaced (on a 1991 Isuzu Pickup, 2.6l 4cl 4x4) the clutch, pressure plate, throwout bearing etc on the transmission. We have also replaced/rebuilt the master clutch cylinder and slave cylinder for the clutch. Everything is seated correctly and the clutch pedal returns to its original position after we bleeded the line for the clutch. Our issue is that when we start up the truck and engage the clutch pedal it still will not allow the gear to be engaged. Do you have any suggestions?

Answer
Well the clutch could not be releasing completely. Uh loose or damaged shift linkage. Insufficient oil in transmission. Debris and or water in transmission. Also worn or damaged striking rod. Sticking or jammed gears. Let me know if this didnt help though okay? got lots of know how and books okay?