Hmmm, doesn't seem quite right there Len. Ya either got the wrong pistons, wrong block, or wrong measurements. Are you by chance measuring the top of the piston? If so, not a good place to measure. If you have skirt protection on the pistons (like Sealed Power), then be sure to measure the bottom skirt below that coating (don't measure the coating). Otherwise, measure the middle of the piston.

Just curious, are you using a caliper, micrometer, bore guage?