for version 5.2 SBFS normally located and hiden as file system in c:\safeboot.fs (depending on how you configuration)
You can mount this to other drive with wintech after you;ve authorize
No authentication need because SBFS is map & write as FAT16 on hardisk.
In certain case even i delete safeboot.fs i still can read my sbfs because physical sector still exist (you can check this SBFS sector information on SBR - disk information in disk information)
Warning Note: Even you can mount SBFS DO NOT edit SBFS manually because it will caused it written to some other sector on your hardisk and this will mess up MEE pre-boot authentication.