Thanks for all the hints!
Unfortunately I just had to abandon the project, as the amount of time I can spend on this is limited. I just couldn't get my MacPro to recognize either the CD drive or the hard drive. Using external CD drives I came a but further but I cannot do anything when my hard drive or hard drive driver, are not detected.
So for now I go with fink and other tweaks to make my MacPro usable for science!