I have an ICD ShuffleBoard that I got in an A500 with an AdSpeed/IDE. I'm setting the AdSpeed/IDE to use a CF card rather than a physical harddrive, so I won't need the ShuffleBoard anymore.
There are jumpers on the board, it looks like it might be possible to hook a switch up to enable/disable the DF0/DF1 swap. I don't have the manual and the host system is in pieces, so I can't be sure. If so, it still means cracking the case open, but leaves you with a real working floppy in the system too.
If you're interested, I can juggle spare parts and do some testing.
-Justin