Hi!

I think VGA-Copy can do what you need. 
If you create a new floppy for your a: drive (that is the 5 1/4"), turn on
the "modify" switch of vga-copy.
When you boot using this diskette, a message appears:

This is no system disk, you can
1) replace disk with another,
2) boot from Harddisk or
3) switch drives and reboot (that is, a: becomes b:, b: becomes a:)
Type your choice:

When you select the third item, you can boot from b: which is now called a: .
Seems to work very good, for example booting drdos6 from the installation disks
in 3.5" format was no problem for a friend of mine (I have only a 3.5" a: drive)

Hope that helps
Robert

P.S.: VGA-Copy is shareware, so it's easy to get. Newest Version seems to be 5.0 .

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