I have some heads with the shorter intake ports but have the higher exhaust ports. C6TE-G i think they are. Buried on a shelf or i'd look right now. In 66 i think all combinations of intake and exhaust ports were available. Aren't the -U the ones with the low exhaust port but tall intakes?
It's been about 6 months, but I had a set in my hands and they sure looked like a C8AE-H or D2 intake/exhaust, only reason it surprised me enough to remember is that I thought it was odd that -J,-R, -U had a completely different configuration in the middle of the revisions. I am not 100% sure though
I will say though with the emissions/short port, ported to loosely a medium riser but with a CJ valve, you get a nice fast port. If the C6TE-G, or any other, had the better exhaust location, could make a nice street head
