Here's what some of the guru numbers mean:
0x80000003 /* Illegal address access (ie: odd address access) */
0x80000004 /* Illegal instruction */
0x80000008 /* Privilege violation error */
An illegal instruction error could be caused by a software malfunction, not just a hardware malfunction.
Have you tried a different disk? Is the WB on that disk modified (perhaps something is running in the SS that's causing the trap) or an exact copy of a CBM disk?
