looking at the pic s ----it seems there is a lot of end clearance on the top ring but you say it is only 020---piston looks like a lot of clearance at top and you say you can rock it in the bore?? wrong size maybe???
Other things I have seen---wrong rings in wrong groove, rings upside down--all will result in lots of leakage

If you are going to just put back together change holes to see if problem moves