.007 on the worst piston is definitly loose for cast pistons ( I run almost 007 on my race motor with forged pistons) I would get a set of .005 over rings and file fit them, at least you wont have a ton of end gap on the rings. you also could go 030 with a set of hypereutectic pistons for not a ton of money if you wanted to just do it 100 %
