It's a prefab unfortunately. I've always ran custom ported,but no one wants to build them anymore for under the seat of a pickup. It's a little more time consuming that a typical box. So my hands are kind of tied.I see, so the box is already made. I had to go back and re-read.
That ones in the mix as well. The inverted surround gains a little clearance on the down firing aspect of it.Sundown SD3.