Armornut - No problemo. When it comes to quirky humor, I am ALWAYS there!
Gamera - There were no plans that I could find, nor were there any official dimensions, so yes I "winged" it! Back in 1988 I made these sketches:
The sketches were freehanded with the focus only on getting the proportions about right. I just decided on a desired span for the finished model and went with that. I had originally decided the scale was 1/200, but I recently cross checked a bunch of stills from the movie and came up with a wingspan of 570 feet, making the model 1/250.
Anime is maddeningly difficult to pin down size, since they will often increase or decrease size for dramatic effect. But I used the 1/72 Tsukuda/Bandai Nausicaa Gunship for reference, and calculated how large it would be in order to fit within the cargo hold, as seen in the movie. When scaled to 1/200 I was dismayed to learn it would not fit! So I just "moved the goal post" and set the scale to 1/250, which would allow a properly scaled Gunship to fit.
While performing the cross check, I calculated the Tolmekian Corvette would have a span of around 135 feet, and the Pejite Barge was around 160 feet. What this means for me is that 1/72 models as I originally planned were out of the question, and they would be 1/144 scale instead. At 1/250 scale, they would be too small for my taste. I might keep the Pejite Gunship at 1/48, but I am inclined to match the Nausicaa Gunship in 1/72. So many projects, so little time.
In the mean time, the freight train continues forward. Pesky project-torpedoing underside of inboard flap, now properly covered: