I found this image on Toho Kingdom Forums a couple of days ago. It’s an old style guide for Godzilla: The Series. I believe the image came from Wikipedia judging from the image URL.
It even shows size comparisons for some of the monsters, namely Zilla Jr., Cyber-Zilla, El Gusano, and C-Rex.
According to this, Zilla Jr. in his theropod stance is around 225 feet tall at the tallest scute, and Cyber-Zilla is of course the same height. That means they’re taller than 225 feet when standing straight. That’s quite a bit taller than their supposed height of 60 meters, though that was probably measured just up to the shoulder in theropod stance.
Interestingly enough, El Gusano slouched over is just shy of 300 feet tall, and he’s quite a bit taller when standing straight. That makes El Gusano almost as big as Heisei Godzilla!
