Today I removed the nuts on the upper engine block studs and removed the rocker arm studs from the lower engine block studs. Everything came off without trouble except for the upper #3 nut/stud on the left hand side of the motor (looking down on it from the harmonic balancer pulley end).
The end threads on that upper stud were so rusted together that there was no way for it to be cleaned and reused, let alone remove the nut. I wound up unscrewing the engine stud itself, which did not strip or twist. There is a small chance I guess it could be reconditioned, but I have my doubts. The availability of the upper studs may represent a problem.
It's an obstacle which I will overcome.
