The boost gauge doesn't go on the air box, that's the suction side. It goes on the pressure side, usually on the pressure chamber/intake hat. On my Hypermax it's on top of the chamber, on my ATS it is behind it.
That IS the pressure side on the Banks gen 1 & 2.
The gen 1 has the intake hat and airbox cast in two seperate pieces. It has the round edges on the air box lid and uses a 3" tall air filter.
The gen 2 intake hat and air box are cast as a single piece (this is the one 7.3IDI has and the same as the one in my pic). This one has square edges on the air box and uses a 3 1/4" tall air filter.
Another thing to note (gen 1 & 2) is that the air filter works "opposite" to what we think is normal in that the air enters the inside and is filtered as it moves to the outside of the filter.
On some of these there is a hole tapped for the boost gauge but it is in behind everything beside the connection from the compressor to the air box/intake. It can be very awkward to get to.
You must be registered for see images attach