The DOS SYS command will make the drive bootable. It should be on the boot diskette.
http://www.computerhope.com/syshlp.htm
If you can do that you could copy the autoexec over and edit it so the paths relate to C: The CD Rom drivers would need to be copied to C: too obviously.
It would only work if the C: partition was less than 2Gb and formatted as FAT. But you could change that later after installing ME.