Switch Windows 8 from a hybrid MBR/GPT => GPT only on Macbook Pro Retina

Question

I used DiskUtility+Bootcamp Wizard to setup my hard drive for Windows 8 (final MSDN). Somewhere in that process, the Apple tools turned my GPT disk into a hybrid MBR/GPT. All four of my MBR's primary partitions are consumed as follows:

1. EFI partition
2. HFS+ partition (=encrypted, therefore ="Apple_CoreStorage")
3. HFS+ partition (Recovery partition, contains unencrypted Mac bootloader)
4. NTFS partition (Windows8 all-in-one partition)

So when I try turning on Bitlocker in Windows 8, it complains about not finding a System drive. I know on Windows 8 the Bitlocker setup (via right click disk->turn on bitlocker) tries to create the 200(?)MB system partition if it is missing. However with all 4 partitions filled I suspect it can't create system drive => it can't find it => throws back an error like BitLocker Setup could not find a target system drive. You may need to manually prepare your drive for BitLocker:

I've already tried disabling hibernation, swap file etc. Now I'm thinking that if I were to get rid of the MBR scheme altogether, perhaps I can be alright within the GPT world without MBR's 4 primary partitions limit.

So, how can I get rid of the MBR tables on the hybrid scheme in a manner that still leaves Mac OS and Windows 8 in working conditions?

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Details:

Hardware is the MacbookPro Retina.

diskutil list output

sid-mbpr:~ sid$ diskutil list
 /dev/disk0
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *251.0 GB   disk0
   1:                        EFI                         209.7 MB   disk0s1
   2:          Apple_CoreStorage                         160.0 GB   disk0s2
   3:                 Apple_Boot Recovery HD             650.0 MB   disk0s3
   4:       Microsoft Basic Data Win8                    90.1 GB    disk0s4

GPT vs MBR addresses

sid-mbpr:~ sid$ sudo gptsync /dev/rdisk0
Password:

Current GPT partition table:
 #      Start LBA      End LBA  Type
 1             40       409639  EFI System (FAT)
 2         409640    312909639  Unknown
 3      312909640    314179175  Mac OS X Boot
 4      314179584    490233855  Basic Data

Current MBR partition table:
 # A    Start LBA      End LBA  Type
 1              1       409639  ee  EFI Protective
 2         409640    312909639  ac  Apple RAID
 3      312909640    314179175  ab  Mac OS X Boot
 4 *    314179584    490233855  07  NTFS/HPFS

Status: GPT partition of type 'Unknown' found, will not touch this disk.**

**: Ignore this message, the gptsync tool is old and doesn't understand the UUID for "Apple_CoreStorage" / FileVault2 partitions. Since LBA addresses are alright, safe to ignore this message.

Answer 1

Not an answer in the strict sense to the specific question. However, as a user I bypassed the need of the answer by converting my Windows 8 system into a virtual machine on the Macbook Pro.

However, I would have tried the following if I hadn't abandoned the original question earlier (to save time!):

1. Allow Bootcamp to create the Windows7/8 USB bootable disc
2. Allow Bootcamp to create the 4th partition (as primary)
3. Boot the Win7/8 media
4. Delete the bootcamp created bootcamp partition
5. In the just-created-free space, create 2 extended partitions (one system, one boot)

I'm not 100% sure if the Windows system partition** (1st used during bootup) can be a logical partition or not.

** Per MSFT's naming convention, system partition boots the system and the boot partition contains the system (c:\windows) - go figure!