Not sure why you would use a screwdriver?
The 194-292 heads has threads like a bolt, but has no head.
It unscrews like a stud would.
I am speaking about the 194,230,250,292 heads.
No description of what engine.Is the alignment dowel like the one used for the cyl head?
No threads?
MBHD
i also use vise grips but with a screwdriver inbetween as a pry. twist the pin while prying out.