I am wondering if squirrels can be litter trained? Anyone tried? How did it go?

My little Maggie tries very hard to keep her "nest" aka cage clean by pressing herself against the bars and shooting her pee and poop out onto the floor. I get this and know she is protecting her nest, and am okay with it (even if is is my bedroom floor and getting increasingly closer to my bed as she gets older and better at aiming ) but would love to know if there was a way to encourage her to use a specific spot in the cage. Or is that a no no because I am hoping she will someday become a wild girl?

I know with rats, hamsters, ferrets etc., it is fairly easy to do - anyone ever tried with squirrels?

If not, any suggestions for keeping her from peeing all over my room?