Yeah, I would put Gohan at Yamcha's height easily. I was flipping through the Ma jr manga and Goku is freakin short. He's barely taller than Krillin and Bulma and much shorter than Yamcha and Ten. Ten, throughout much of Dragonball looks to be just over 6 feet to being way above 7 feet. So yeah, Ten seems way too big, kind of like in that sticker of the gang I posted earlier. He's freaking huge.Based on how much taller he seemed than Vegeta and the females, as well as how he occasionally looked noticeably taller than his dad, I had first guessed that teen Gohan was a six footer, or maybe 5'10-5'11. Ten just seems too big; often his height advantage on Goku is more pronounced than the supposedly 7'6 Piccolo's.
If anyone does say Goku grew though, I don't know about that since his height with Yamcha and Krillin remain fairly consistent to where Krillin is at Goku's shoulders but Goku is barely above Yamcha's shoulders.
Maybe the theory that Namek's continue to grow since they reach adulthood fairly early isn't untrue. King Piccolo looks to be 9 to ten feet tall in most instances but in his youth seems to be more around 7 feet tall. Ma jr looks to be around 6'6" at first but by the time the Buu arc rolls around seems to be at least 7 feet tall.
However, the height chart of him for the Tree of Might, he looks to be what he is supposed to be and that is 7'4".

