GT40P Head question/tech info needed.

Hi everyone. I race a circle track truck out here on the west coast. We just got done winning our 3 straight championship. The series I race in impounded my engine to tech it. We are required to run the GT40P heads on the Fords. The problem I am running into in tech now has to do with the GT40P head castings. I have one head the has a small raised circle casting in the upper part of the intake port & I have one head that doesn't. The tech officials think I acid ported the one head that doesn't have the raised circle casting on it. I promise you I didn't! What I have come to find out after looking at all the heads I have (I have 10 of them) is that the heads that have a date code that starts with "7" have this small raised circle casting & the heads that have a date code that starts with "9" don't have this small raised casting. I had one of each on my engine. I'm trying to locate any information I can or someone I can contact at Ford about this difference in these two heads so I can prove this is the way they came from Ford. I already contacted Ford Racing & they couldn't help me because it's a Ford production head not a Ford Racing head. Any info you can give me will be greatly appreciated.

Thanks, Jeff Williams

Jeff Williams Racing