Adjusting hydraulic lifters on a running engine is an exercise in frustration- - - - -and it makes the floor slippery. You're not preloading the lifter enough- - - -it needs at least one full turn of the adjuster after the slack is removed from the assembly. Be absolutely sure the cam is on the base circle by watching for "split overlap" on the companion cylinder- - - -intake opening and exhaust closing, called "rocking" .
#6 rocking, adjust #1
#2 rocking, adjust #5
#4 rocking, adjust #3
#1 rocking, adjust #6
#5 rocking, adjust #2
#3 rocking, adjust #4
You can adjust all the valves in two turns of the crankshaft, and they'll all be right.
Jerry