short circuit in starter wiring on k11 2002

[Jak2]

Hi, My micra k11 2002 micra was blowing the main 30A ignition fuse at the battery area when the ignition key was turned to the start position. The fault was traced to a short circuit in the black/red cable from the ignition switch to the starter solenoid. This circuit was rewired and is ok now but I would like to know where the actual short could be in the ignition/engine harness without stripping the whole dash out. Can anyone help or is this a common fault with K11's. Thanks