err, this might sound BS considering I have not work on valve clearance on a puch rod engine, yet. But, if you put your crank at TDC or BDC half the valves will be at its rest (for example: intake cyl 1 $ 4 closed, outtake valve 2 & 3 closed at TDC, turn crank another 360 degrees then the combination of opening will be the oppsite).
Then, use the filler gauge to adjust rocker to a spec. Make a note of which ones you have done at TDC and make sure all of the are done. I can't remember on top of my head which cylinder opens up at TDC, but you only need to turn crank twice. Once to find out TDC and turn 360 degrees.
Am I bull shitting or didn't I understand what you were trying to ask?