I am in the process of trying to "legalize" busking in Raleigh, NC. Currently there is limited busking within confined areas, and not the parks. I am trying to change this.

I am looking advice from individuals who have done this in other areas to provide basic guidance. I promise not to make myself a pest.

Yes, I am familiar with the First Amendment.

Contact the Busker project
they have been also working on this and may have some insight for you
https://busk.co/

You might want to contact local chapter of ACLU. If you google "ACLU Busking" you'll see they've filed quite a few lawsuits on behalf of buskers.

There's one I saw about ACLU getting buskers allowed on National Mall. There's an attached PDF of letter that has a ACLU Staff Attorney. If that person is still around (it was back in 2010) they might be able to help get you connected in your state.

https://www.acludc.org/en/cases/busking-mall