440 power gains/ aluminum head advantages?

i have ball end pushrods. how do i measure lift from pushrod without rockers on it? i'm wondering if i could just put the dial indicator on the top of the lifter and rotate the engine... hm. i took an old hydraulic lifter i had and tac welded the seat to the lifter and installed it but something has to be off because the rocker on that lobe has no play even at the very bottom of the cam lobe. can't move it side to side at all. like it's holding the valve open a little all the way around the lobe. there is no weld or splatter at all in the top of the lifter where the pushrod sits so i'm not sure how it could be like that. i might just try to tac weld another a try it to see if it works normal. all this fuss i might also just break down and buy a valve spring compressor for head on engine and change it out to the lightweight spring that came in my degree kit.
Put it on lifter down in the valley multiply by 1-1/2 there your lift. Or use a cupped pushrod, dowel, brake line, copper tubing, laying against the rocker shaft (keep it straight up and down) all measurement can be taken off the lifter. On what you made you’re getting into preload of lifter