The same companion cylinder procedure works on hydraulic lifters. Instead of using a feeler gauge, just tighten the adjusting screw to barely eliminate the slack in the pushrod/rocker arm/valve assembly, then tighten the adjusting screw another 3/4-1 turn to slightly compress the plunger on the lifter. Then lock the jam nut down. The factory instructions say to use 1 1/2 turns of the adjuster screw, but I've found that's usually a bit too much. Once you get thoroughly frustrated with trying to keep stovebolt hydraulic lifters adjusted, bite the bullet and buy a solid lifter cam.
Jerry