If you can get the adfs onto the amiga, then unless you ended up with an amiga with an HD floppy disk drive (A4000s and Escom A1200s I think), you can use a HD floppy disk in the amiga and it will just think it's a DD disk because the amiga can't check if it's a DD or a HD, as far as the amiga is concerned they're all DD disks that you stick in... and if worst comes to worst, you can can just tape over the extra little hole on the HD disks and turn them into DD disks :-D
From what I remember, most/all amigas can boot from the external diskdrive port.
Sitting here looking at the A4000's pin assignments for the diskdrive and parallel ports I think the parallel port has enough pins, as long as you're willing to use Busy and Paper Out and not want to have more than 1 amiga "drive" ;-) Otherwise, a little board may have to be made that answers the extra pins of the diskdrive...
The software shouldn't be hard, as far as I know the code for mounting and using adfs is free, so the main body of coding a person would have to do is translating the parallel port into commands to access the mounted adf and vice versa...
Once I get my own workload under control I might actually give this a go, it sounds like a good challenge :-)
