I just got this 77 440 and am wondering about the stamping on the pad. It says 7t 40 EH. I can see that some of the letters have been worn away which explains it saying 40 instead of 440 like it does on the side but the only stamping code that i can find with an "H" in it is "HP". I didnt think that HP engines could come with cast cranks. Does anyone know what this could be?