-Edit /Users/<user>/Documents/Parallels/<VM Name>.pvm/config.pvs
-In the <hdd> section, find <SystemName>
-Change "/dev/disk0" or a similar value to the full path of the disk image in the same directory. In my case it was "/Users/<USER>/Documents/Parallels/My Boot Camp.pvm/Hitachi HTS############.hdd"
-Restart the VM
Why does this get overridden every time I edit the config in Parallels?
Thanks for figuring that out. I need to try that when I get home tonight!
Though, I am using Bootcamp - so I'll have to be careful.
I tried to reconfigure the boot camp vm to try and get it to see the right disk, but it certainly won't change anything in the GUI - hacking the file is a good idea.
I tried Jason's trick for fixing broken bootcamps, but sadly it did not work for me. I deleted the config and re-created from scratch. I guess the trick for now is to never edit your bootcamp/VM configuration once it is created....