There are no tunnel rams for the high port heads that I know of.
I have 2x4, 600's on my 347 on my '68 GT350. They are very impressive. Like you said, rpm through the roof.
I'd rather have 1 primary carb then 2 but yours works too.
It uses the Trans-Am Mustang high-rise 2x4 intake and the 427 dual quad linkage with the carbs mounted backwards.
You can cruise around town all day a just a 2 barrel. When you open them up they pull very hard.
Hum, this was a good way to get you to post pictures of your intake