1975 1.8L 914 Cylinder Heads - Question Options

[Aayala]

Hello! First post here… I was wondering if anyone could verify if this looks like some sort of repair done by someone on the cylinder heads of my 1975 Porsche 914 1.8L engine? I am starting the process of tearing the engine down because it was seized. I got pretty far as to remove all of the cylinders including the one that was seized. Had to soak it in some mystery oil for over a day and finally took it apart. The cylinder heads and cylinders to my surprise on one side looked pretty new from the inside, on the other side however not so much. Cylinder #1 was the one that was seized and the rest looked in good condition. I have the receipts from 1990s that the engine was rebuilt by a Porsche mechanic shop in Austin along with all of the part numbers to confirm. What did catch me by surprise was that upon closer inspection of the cylinder 1 head, the exterior ring looked different than all others. Can someone please let me know if this is some repair job done and this is what caused the failure of the engine most likely? Seems like a coincidence that this was the only cylinder with an issue and the head was also different than all others. Would love any feedback anyone could give! I’m probably replacing the head itself but if that is not the cause then I would see how they look after cleaning. Thank you again in advance!