OK. In conclusión the .55 inch or 9/16 method is crap. THe same applies to the plastic tube fastened to the drain plug. I wouldnt like to bend the tab so much as the fuel overflows from the air vent of the carb float lid.

  If crap is that grey area I referred to, then yes. There are many variables in the floats, some that come to mind are, are all floats the same after forty five years, the differences in needle valves, wear in the float pivots etc.

Just bend the tab a little, remove a little fuel from the bowl, reassemble the carb, fire it up, shut it down (choke off), remove domes and pistons, check fuel level in nozzles, if it needs adjusted, just bend the tab a little bit, etc.