'99 clutch disengagement issue

[desertdog]

My 6 speed is having issues disengaging. Truck has 250k miles. Heavy towing 30-40 % of time. Clutch/hydraulic package had 65k miles on it, heavy towing maybe 25k miles. Started having disengagement problems and changed out the hydraulic package. Seemed better but has got progressively worse now (within weeks). Read the threads and some suggestions of pedal to primary pushrod bushing failure and some of possible firewall cracking. Anywhere else to be looking? Thx in advance for any help.