You can go .018 on the second ring or delete it all together. Of course, you are talking a street ride.

I have one 451 out there in a 64 Savoy four door and it runs on the street without the second ring. Now I know I'm going to get killed about this, but before you react, John Erb, long time cheif engineer for KB told me to try it and check the HP production of one of my other engines using the full stack. HMMMMMM a full eight HP and no smoking or oil usage. Since the distance between the bottom and top ring on the Hypereutectic pistons is so long, there is no trouble with rocking. That and the tighter bore they require.... Just a thought. I sure wouldn't use a .013 ring gap for the second ring.

Peace, Rev. Mopar