Removing email from an Apple ID
I know this question seemingly has been asked and answered, but I've tried doing this multiple times and it is flat out not working.
I would like to use my primary email address (call it EMAILP) as my Apple ID for my new iPhone. However, that email address is currently being occupied as a secondary email address for a different Apple ID, which I do *NOT* want to use as the Apple ID for my new iPhone.
How can I remove my primary email address from its link to an existing Apple ID? I've tried to do the steps listed here and now it is no longer listed as an email address for that Apple ID, but I cannot create an Apple ID using that email address as the Apple ID.
This is extremely frustrating, and I do not want to be stuck using a secondary (spam-box) email address as the Apple ID for my phone.
Is there some 'secret' way to do this? The documentation everywhere seems to indicate that what would have been an ideal solution, changing the Apple ID to match the primary email address, exists, and in fact, the website support urges me to do that, but when I click 'save' it doesn't ACTUALLY do it.
Am I doing something wrong, or is the website broken today, or is just whole thing just fouled up?
Any advice appreciated.
Thanks.