Pushrod problem with Speedmaster heads

Large holes because roller lifters are taller. Easier for the manufacturing process to drill round and bigger, than to elongate.
My opinion.

next. I got to figure push rod length.
I have questions on how to determine. the old “stick 2 threads of the the adjuster down”. Jus doesn’t seem like the answer, w all this “china” stuff out there.

I would think the ball pivot should be below the fulcrum center, what ever threads are showing.