I've got an A2090A (autoboot!) shelved, unused for ~10 years when I played with it in my A3k (it did work) - what's the offer? Anything to swap? Where are you at?
I think I might even have a 20 Meg ST506 HDD that should work with it... :-D
If you want to access an old MFM drive it must have been formatted with the very same controller type.