Took the ZF out again. Replaced the 3 finger McLeod, for a Diaphragm type. (less pedal effort, I like it.) New disk again, cleaned everything thoroughly. Replaced the throw out bearing again. Put it all back together, same thing, more than a light shudder when taking off in 1st gear. Reverse too. Wondering what else it could be? Never any problem getting all the gears, no grinding what so ever. I thought maybe the rear brakes were grabbing, no. I expect the car to crawl forward with just letting the clutch out, no gas, and for it to be smooth. My other Pantera's do it. I understand there could be a break in period, but this feels excessive. Driving 500 miles in stop and go traffic will take a year.
I just can't believe anything is wrong in the bell housing. Still, I will take it out again, if I know what to look for.