You may need to setup a second mount file.
Make a copy of CD0 in your Devs: draw and call it CD1. Then open it and change the "UNIT" number, if CD0 is 1 then CD1 might be 2, trial and error on that bit.
Or download IDEDFIX97 from aminet and then use the program to find the drives on your system. That will tell you the unit number too
