Ring end gap

Agreed on not using feeler gages to measure that piston to wall. If you can't do it, pay a shop to. It's that important. Given the ring issue, it should be a no-brainer to have them mic the bores anyway. Something is not right. How did you get the bores to +.040? Did someone machine it for you personally? Did you buy it that way? Did you pull it apart and fine pistons marked ".040"? If al the rings had the same issue in all the bores, either the bores are off, or the rings are off. It's just that simple. I'd cart it to a local shop and have them verify everything for you, or order a .040 over set of file-to-fit rings from somewhere other than Hughes.