For a visual comparision, note the link to Keith Black Chevrolet 327 pistons for 5.7" and 6.0" rods, with 4" bore instead of 3.875" bore of the Chevrolet 250.

327 Piston with 1.385" Compression Height 6.0" Rod (KB154):
http://www.kb-silvolite.com/kb_car/performance.php?action=details&P_id=46

327 Piston with 1.678" Compression Height 5.7" Rod (KB156):
http://www.kb-silvolite.com/kb_car/performance.php?action=details&P_id=44