Exactly, you can tell because it is a small regular oval port with no water galleys at the manifold face.
Attached is a picture of what a real GX head looks like. This is a New Old Stock unit. See the writing on the top? No numbers.
You need to stop the misinformation, whoever is telling you that it is an A14GX engine has no idea what they are talking about. You have an A14T engine, far from an A12GX.