Well i did fix the gash but that was NOT the leak...turns out it is the starboard lower engine mounting bolt...so..is it as simple as pulling the bolt, coating it with sealant and replace?

I would use 4200 and fill the hole after removing the bolt and coating the bolt also. Put it back together and then put a coating on the inside and outside of the bolt. You will get absolutely NO water through that hole again, and will be removeable if you want.

The boat thanks you for fixing the gash. Nothing worse than trailer rash. Luckily, those repairs don't cost much cash. Water intrusion into the wood core of the transom will eventually lead to the demise of the structural strength of the transom. Seal that hole very well indeed. I love the old boats, give us a peek (photo):love: