Have you looked into a Gotek floppy emulator? ?
I fitted one into an S900, and then into my Yamahah RM1X and it worked perfectly in each instance,
It then behaves exactly like a floppy disk (well 100+ floppy disks to be precise)
(looks like someone has already done it :?https://www.yamahamusicians.com/forum/viewtopic.php?t=17483
