Sending the pictured Scott 610 examples to be certified as Scott 613 is an avoidable expense, perhaps better spent on basic reference books about US Stamps. Information about rotary press and flat plate printing and perforations is readily available on the Internet. All it takes is a willingness to spend a few minutes to learn before before posting.
This is exactly what previous posters have described as the problem with trying to measure fractions of a mm (the flat plate is 19.25 x 22.25 millimeters. The rotary plate is 19.25 x 22.50 millimeters) with a ruler:
Look at the ruler at the bottom of the stamp. See how the bar is not parallel with the stamp?
Look at the top of the stamp. See how the ruler extends just a little bit more than the stamp?
Yep, those are tiny mistakes. But they add up to the difference between a lat plate and rotary plate stamp.
Try laying a straight edge paper along the top border of the stamp and place your ruler up to and touching it on the center of the 10mm line and measure toward the 32+mm point. It will be truer than hoping the end of the ruler is true.
Find a 610 side plate block of 6 and compare the height over three stamps. There is no substitute for comparison with stamps that have a known identity. Believing that the height or width of a stamp can be effectively measured could lead to costly errors. Always compare with a reference first. It will save time and money.