3/4 of a turn should have been ok. Use the EOIC method. This way you are sure the valve you are adjusting is on the base circle of the cam. I know many books tell you of the method you used but the EOIC method is fool proof.
Also after adjusting the valves and starting the engine you may have to give it time for the lifters to readjust and pump down. This is normal.
Doing it hot while running is a real pain. That worked with Chevy's where you only turned the nut on the rocker arm stud. With your set up you have to adjust the pushrod which is moving up and down. This is not necessary with hydraulic lifters. Do cold. Adjust 1/2 a turn and be done with it. BUT you have to be sure the lifter is on the base circle, use the EOIC method.
What you did by backing off the valve adjustment on certain cylinders tell me that those valves were not on the base circle of the cam when you did your initial adjustment. Now you have lifters adjusted differently from each other and you do not know exactly where they are.
As a note for others if you have the solid lifters as the earlier engines had. Do this, get the engine hot, turn off and adjust just one cylinder, let the engine cool down (next day) and measure the clearance for the valve you adjusted when hot. This will give you the cold setting and adjust all the other valves to that clearance. Again us the EOIC method. The difference will probably be a few thousands.
There are many video's on youtube on how to adjust hydraulic lifters and they are basically all the same. The idea is to put the lifter plunger at mid stroke so it can adjust up or down. The amount of turns to do this is dependent on the stroke of the plunger and the pitch of the thread on the adjusting screw. This can be calculated if you want but this is getting to anal. I do not know these values anyway to do this, but 1/2 to 3/4 a turn should put you close.