I am the second owner of my 67 Notch from new. When I bought it 10 years ago, it had had a wiring loom fire in the engine bay. A battery had exploded and damaged the engine bay and the front fascia of the car. The bulkhead connector was suspect. Don't know the cause and don't care, there are a bunch of threads here about this modification and after 15 years as a journeyman electrician it all made sense to me. I had the dash out of my car and it was an easy to follow and accomplish mod. I also removed the fusable links and added circuit breakers from the alternator to the battery and from the battery to the interior of the car. (dash) Certainly not a necessary mod but one that made sense to me as I had my car completely blown apart and a lot of folks on this forum recommended it. JMHO