360 hydraulic lifter valve lash

I would not change all the lifters

I'd pull out a known good one or buy a new replacment --just one-- and check it and your old ones against the "bad" one and a "known good" one (that's 4 altogether) for pushrod seat height

Check out a couple of other pushrods, although I guess you swapped em

AND CHECK THE valve stem installed height against other valves