Domain ID concerns when removing a brocade director from a fabric

Greetings,

I am removing a switch from a fabric, as the location is no longer used. 

To complicate things and cause me lack of sleep, the switch I want to remove is the Seed/Principal Switch.

The switch is connected via two ISLs to the fabric.  The fabric has switches set up as:

DCX Brocade domain ID=4 (this is the principal and one I want to remove).

DCX Brocade domain ID = 7

DCX8510-4B - Brocade domain ID = 9

Fabric OS version is v7.0.2c

How do I 'safely' remove the switch without causing fabric issues?

Any input and/or experience shared is greatly appreciated.

-julianne