Before you rip into the valve setting again, I'd warm that thing up to temp. I'm mean drive it some to get it warm if you are anywhere near as cold over there as we are over here. 40-50 MPH wind gusts blew part of my in laws roof off, and the wind is blowing some roofing off my shop. What a pisser.
Anyway, get the engine nice and warm and then set the lash. With the engine warm and the the lifters should have much more resistance when you get to zero lash. You shouldn't need to touch the pushrods at all. Just back the adjusters off and the down to zero, screw a 1/2 turn in, lock it down and go to the next one.
