How to add DOS to a Windows 9X system and DualBoot

This information was written in 1996. It has only been tested with Windows 95A, but see q155364.
It is assumed that C: is FAT16, not FAT32 (if this is attempted with >= 95B).

01) Boot to DOS Disk
02) Rename MSDOS.SYS and IO.SYS to *.W40
03) Copy AUTOEXEC.BAT & CONFIG.SYS to *.W40
04) Add a fully functional DOS Directory
05) Edit AUTOEXEC.BAT & CONFIG.SYS to reflect the DOS operating system
06) Sys the Hard Drive with DOS 6.2
07) Reboot to DOS to confirm everthing is working
08) Boot to WIN95 Disk
09) Rename IO.SYS MSDOS.SYS, COMMAND.COM, AUTOEXEC.BAT, & CONFIG.SYS to *.DOS
10) Edit MSDOS.W40 to include the following options
[Options]
BootMulti=1
BootGUI=1
BootMenu=1
BootMenuDefault=8
BootMenuDelay=7
Logo=0
Network=1
11) Sys the Hard Drive with Windows 95
12) Reboot

You will now have the following equivalent files depending on which operating system you are in.

DOS

WINDOWS
D1 AUTOEXEC.BAT    929 W1 AUTOEXEC.DOS   929
D2 AUTOEXEC.W40   373 W2 AUTOEXEC   BAT   373
D3 COMMAND.COM   54,645 W3 COMMAND.DOS   54,645
D4 COMMAND.W40   92,870 W4 COMMAND   COM   92,870
D5 CONFIG.SYS   999 W5 CONFIG.DOS   999
D6 CONFIG.W40   306 W6 CONFIG.SYS   306
D7 IO.SYS   40,774 W7 IO.DOS   40,774
D8 MSDOS.SYS   38,138 W8 MSDOS.DOS   38,138
D9 MSDOS.W40   1,704 W9 MSDOS.SYS   1,704
D10 WINBOOT.SYS   223,148 W10 IO.SYS   223,148

Also see http://www.bcpl.net/~dbryan/directboot.html