I recently removed my 340 for some work and while going over the heads I noticed a small part of the intake runner on my left head (340 X heads) had been "punched out" along the side wall at the bottom of the valve cover bolt hole. The hole is about the size of a small pea. I assume somewhere in this head's life someone used a too-long valve cover bolt or something (wasn't me). I have no idea how long it's been like this. When I shine a flashlight into the valve cover bolt hole, the light comes out into the intake runner of the head. I immediately checked all of the other valve cover bolt spots inside both heads and only this one is punched out. I checked down at the valves for the metal that got punched out and it's long gone. How can this be fixed? Can I just put a dab of high temp epoxy? It's not affecting any of the valve cover bolt threads. The photo with the screwdriver, it's a very small screwdriver.