I have a hemi carb number 4139 s dated a6 also have one dated e6. The first dated a6 has 2 holes on each corner to mount it to the manifold. The other only has 2 holes on two corners to mount it. Was there a change or did someone just drill the other 2 holes. I have other hemi carbs they all are the same as the e6 carb with two holes on two corners.