Rocker Assembly

Not to hi-jack the thread but this caught my interest. I understand torqueing the shaft bolts to 17 ft-lbs but, How do you gauge this correctly if your installing the non-adjustable rockers? The spring pressure on the rockers has to throw this off a bunch. I tried to figure out how to install the shafts and rockers without the pushrods first and torqueing everything before putting in the pushrods but, I keep coming up with a zero? Unless your using adjustable rockers I can't figure out how this would be done. Can someone help me here for future builds?