I certainly would not have done this. I had a BPPC with SCSO, it happened something similar to whathappened to yours, but removing the SCSI was the worst decision I made, it never worked again. Maybe you get lucky though, in order for the A1200 to boot you must disable SCSI by pressing the 'S' key when cold /boot or resetting the machine. If I were you, I would try to contact amiga.fr to fix my board. Thy're not at amiga.fr anymore, they changed their web address but I'm sure they're still around.
As for the firmware, afaik, it's the same.
Good luck,
D.
