registering as a member of the SCCA and getting a permanent number.
Numbers are handed out on a Regional basis, not National.
You're on the right track though.
If you register with an SCCA Region, then you can pick from one of their available numbers.
You should also note, when you race in another Region's event,
their members will have the number preference, and your's may be taken.
That's why my 2 numbers (38) are separate.
I can be either 38 or 83.