Well, some good news on this forum. Took my 22 week young pullet, Blanche, to my vet yesterday to evaluate/trim her crossbeak. He used a Dremel and took just enough off, top and bottom, to give me a tutorial on how it is done. Said she is in quite good condition despite her eating challenges. He even lightly trimmed her toenails! I think I'll be able to continue the trimming on my own once I have the correct tools. She was a very good chicken at the vet clinic!