Timing Cover Coolant Leak I've Never Seen Before

The cover on my 273 started leaking it was a pin hole. My said put a little JB Weld and it will be fine. I couldn't do that and I pulled the cover. Glad I did, the inside looked like the surface of the moon. The inside was heavily deep pitted all over. Electrolysis is taking place and attacking the weaker metal the aluminum. If it was and outboard motor at a dock you attach a zinc tab. I just added a couple of extra grounding cables the engine along with a kill switch. We'll see how that works.