My point was I wouldn't worry about the rod length, order the pistons for your combo without running the pin into the rings if possible. Either a 6.7 or 6.8 should work OK, a 6.8 will give you a 1.2125 pin height, 6.7 is 1.3125. By comparison, I have a 447 SB2 with a 4.125 stroke, 9.320 deck, 6.125 rod and roughly 1.13 pin height. I am building a 460 SB2 with a 4.25 stroke, 9.5 deck, 6.2 rods, and depending on final deck height, around 1.18 on the pin height. Give the piston company you chose all your final specs and they will tell you which will be the most stable piston, and get the corresponding rod.