In this video below, Rob measured just over 5ft 8 3/8ths, and Big Lewis measured almost 6ft 1/2 inch, so the height difference is an example of a good 4 inches.
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A 2 inch height difference is still quite noticeable. In an earlier video, Rob was 5ft 8.25 and Lewis 5ft 10.25, so the clip below is a perfect example of a 2 inch difference in height:
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