earth leakage in ignition system

[Justy]

Im not a hugely technical person but have had a bit of help on this issue- background I noticed pitting on my lower unit on my BF90 its very low hours under 50 I didnt buy it new so I dont think the warranty is still in place. Anyhow with the negative battery lead disconnected from the motor and the ignition on I hooked up a test light to the disconnected end of the negative battery lead and put point of test light on hull and the light goes on- so the hull is live there is a leak somewhere in the ignition system i believe. I then disconnected the Top connection on the starter motor/relay and the test light stopped- I get the test light to stop also when I pull out the main 30 amp fuse fuse 6 I believe. Any advice or should I just take this straight to a marine auto electrician? Problem is I live in a really remote area - 2 hours from the nearest service agent.