Dump your existing live DB to a .sql file (excl the system tables) and then using a suitable text editor, do a Find and Replace on all references to the Database Name in the .sql file and rename to whatever the new database name is
Create new business space, put it into TEST and then restore the newly edited .sql file. This will overwrite any existing test data in the CRM sample. If you wish to add the CRM test data back you need to run the related import process again