Not really as I am not a spark but what I would likely do is try and remove all circuits and enable one at a time and see when/if the fault occurs.
I would look at the wiring to see if there is some damage to insulation which may allow the current to leak to earth, something like a nipped cable or insulation that has been cut by swarf. It may be hard to find, especially if the problem is in multicore cable as you may not see any damage from the outside but if you can narrow the problem section of wiring down to a specific area it will be easier to find.
Hood