Magnum slug weight vs...
Just took a factory stock one apart, standard 4" bore, and weighed it. This one, for the record, is 1999 model year 5.9 Magnum. Piston weighed 469 grams, pin was 135 grams, and ring set was 39 grams. I don't have any 2003 model year parts to test for the original question, but this should get us close enough to be dangerous. I plan to use the Icon forged pistons, but don't have them yet and don't know the weight of the ring set for them.