I agree with you, with the following:

Quote Originally Posted by JeffYoung View Post
...radiator has to be the forward definition of the engine compartment. Otherwise, you could use the void between the grill and the radiator on pretty much any car to make an effective and never intended cold air intake.
This is supported philosophically, in that the regs do not allow you to make a shorty radiator and leave a hole next to it for air intake. It would be nice, howver, for that to be explicitly clarified in the regs (easy to supplement the "engine compartment" definition within the ITCS.)

Based on that, he Jackson intake is not legal as it extends past the rear of the radiator. Cut it off there and probably legal.
I agree that the intake portion of it should be behind the plane of the radiator. However, there is no restriction to the mounting portion of it needing to be behind that, as long as air is not taken in from there.

GA