If You're going to run any kind of real cam lift, You will definitely want shorter pushrods, and You will want to make sure the head bolts will not bottom before coming up to
torque. Grade 8 washers will handle that........
Agree about the head bolt, and washers. Disagree about the pushrods. Every thing else staying the same, except for the cam, you might need longer pushrods, with a big cam. The nose of a cam stays at the same hight from the center of the "stick". To gain lift the base circle gets smaller, which locates the lifter lower.
When cutting the deck and/or head, then shorter pushrods might be needed. As with anything else MEASURE,MEASURE,MEASURE.
One of my engines, has .125 cut from the head, and has a .520 lift cam, and uses stock length pushrods. The head mill, and smaller base circle of the cam, cancel each other out.