Interesting Letters on the Hood of my Newly Acquired Formula S

I've previously posted a few pics of my newly acquired Formula S 4 Speed. I'm intrigued by the 3 letters on the front edge of the hood - E A O. They are probably previous owner installed but the holes were very precisely drilled and the one long leg on each letter has an insert in the hole. The car did have one previous repaint about 35 years ago (think poor Earl Scheib). The A has the part # 9770893 and 63103 on the backside. The other 2 letters only have a "G" on the backside. The "O" is a different size than the "O" in Plymouth on the deck lid. Any thoughts other than previous owner installed??

65cudaEAOpic1.jpg

65cudaEAOpic2.jpg

65cudaEAOpic3.jpg

65cudaEAOpic4.jpg