How do you make pie with Citron watermelon (not just the rind)? Citron watermelon (AKA Pie Melon, Tsamma, and Colorado Preserving Melon) is said to be useful for making pies, preserves, jam, pickles and such. It is not used for fresh eating, typically, and is hard all the way through even when ripe. The interior is supposed to be high in pectin. (I believe Tsamma sometimes refers to a similar kind of melon that may have different properties, FYI.)

I grew one plant that got 9+ melons (the Red-seeded type from Baker Creek). So, I'm wanting to know how to make them into pie, since it sounds fascinating, and I love pie. How do you make pie with the inside of the fruit? I know there are recipes for watermelon rind pie floating around there, and those may work with these rinds, too, but it's mostly the interior that I'm concerned about. If your response involves both the interior and the rind, that's fine.
...NadjaCS seems to have already answered this question above, but here's a link to a website which explicitly gives a recipe for a pie-melon pie using diced and flavored pie melon. It also has a link to an antique recipe for what appears to be candied pie melon slices; I'm sure you could use those slices in place of the base for some other fruit pie.

https://ganga108.wordpress.com/2013/08/30/pie/