The clock source jumpers (INT/EXT) are probably correct, because if they aren't, you will get no boot up at all.
As mentioned, the most likely problem is the 68060 CPU library not installed. You should have been given an install disk with your PPC board, it essentially installs a dummy 68040.library which points to a 68060.library.
If you require the install disk, contact me via email and I can send you an image, or just the CPU libraries required.
Anthony.