Take three pistons and lay on their sides, place a wrist pin half way in each outer piston and the other half in the center piston. The center piston notch up, the two outers with notch is down. If the hole is offset, the center piston will be up off the table. If not, turn the whole mess over and recheck. No measuring needed this way !
We used to install our Pontiac pistons on the wrong side ( backwards ) when racing, this makes the piston dwell longer at TDC which makes more power. Never had any problem with them. Not sure it really worked, but the Chrysler guys did it, so we followed them.
