Hi, I have this drive "Sony 920MPF z/161" the board looks identical to yours, I tried to make the mod and then tested on my A500, it makes the "asking disk" sound, but when I insert a floppy it tries to read, make a few tries and then stop.
I'm not very good soldering, I break the 0 ohm resistor and put a tiny piece of metal instead, but this is so small I can't tell if it's properly fixed.
Thanks!
BTW this is my first post on eab, and sorry for my english