[350HP930]

What you want is each opposed cylinder piston and pin (ie 1&4, 2&5, 3&6) to have matched weights. For that reason you would want to balance each set that is already close in weight to each other so that the weight removal is minimised.

If you took the heaviest and lightest piston and tried to match them up you would have to remove more weight than if you took each closest pair.

If you look at my piston weights that I posted above they are listed as best matched sets. Do the math yourself and you can see which method is more effective.