Only for the record, since NT 3.1, ALL NT systems were designed to be installed on logical volumes inside extended partition.
I.e. since 1993/1994, you only need a small partiton. Primary, Active
with filesystem FAT16 if you want to boot DOS up to 6.22 (and conversely Windows 3.x)
with filesysystem FAT32 if you want to boot DOS 7.1 up (and conversely Windows 9x/Me)
This small, active, primary partition will hold also the NT bootmanager(s), i.e.:
NTLDR, NTDETECT.COM and BOOT.INI for Windows NT up to XP
BOOTMBR and \boot\BCD for Windows NT from Vista up
And any number of logical volumes, in each one you can install a different NT version.
The hiding has never been *needed* unless you wanted (for *whatever* reasons the OS drive letter to be C: on different OS's).
Now go back in time and read:
Then come back here and ask your questions (if any)
 actually you can install also Windows 9x/Me on a logical volume inside extended (keeping the DOS files on the small primary, active partition), but it is a relatively long and complex procedure