I don't know why you would want the lifter to bleed down. That seems to be the exact opposite of proper advice, unless you subtract the lifter collapse amount from the pushrod length you find with the check rods.
It seems to me you really want the lifter at operating height. It also seems the very last thing you want is to center with the lifter in an abnormal plunger height, and not even know what the state of collapse is when you check (which is what a bled down lifter would be doing).
This is the whole reason behind check springs. Check springs don't collapse the lifter. They let it sit extended.
So you have some people who do this at maximum lifter height by using a weak check spring or a modified "solid" lifter, which means the lifter is pumped up normally, and some doing the measurement with the lifter at an abnormal plunger height you should never see in operation.
Since I planned on running mine at very slight lifter preload, I put a brass slug in a lifter that set the push rod cup at the planned height. But that is just me. I could be all wrong, and you really want to use a 800lb spring or a dry lifter with normal springs and pick a pushrod with the lifter collapsed, instead of check springs or solidized lifters and the lifter at operating height.