Hello again everyone! I see some of you are a little confused.

So as for husbandry, I measure my temps with a ground level thermostat and hygrometer on both sides of the tank, it sticks to the glass. The 70 degrees is ONLY a thing during the winter months. It is closer to 83 degrees in the summer. And actually, Custard prefers his cold side.

As for his size, I was giving a very rough estimate. Custard is big, and very healthy. The length was something I guesstimated. I had no idea it would cause such a fuss. I've fed adult mice because they are the same circumference as his belly. But since he's so big now, I'm moving to two mediums because that would be closer to 1.3 times his belly size. However, I am considering getting larger prey very soon.

Regarding feeding, I switched to medium mice two days ago. I let the frozen mice thaw in the fridge, then I take them out and wrap them in a heated blanket. When I feed them to custard, they are slightly warm to the touch and a little bit of blood is coming from the mouses nose.
The mice I feed are local, and they keep their mouse scent. Custard always knows where to start eating.
I offer using tongs, and move it slowly along the bottom of his feeding tub. He always gets excited and strikes quickly.

When I fed the two medium mice, I waited about two minutes after the first one was in his belly to offer the second. He only began to twist on the first mouse, and was abolsutely normal on the second.

And on to turning red. As a banana, custard is very light in color. He has always gotten a shade of red during his feedings due to stretching his neck to eat. It does get worse when he twists, though. The red coloring is likely due to stretching or strain.

And finally, the spider gene. Custard, as a baby, had a bad wobble. He would corkscrew and wobble quite a bit, missing his strikes. However, as an adult, he is much more deliberate and rarely misses his strikes. He does not wobble nearly as much, and only occasionally disorients himself while his head is in midair.

He only acts like this at the end of feeding, while he's trying to move it back into his stomach. The twist isn't so much wild movements as it is getting his neck into a kink.

I hope I answered all of your questions. Thanks for the feedback.