I have drawn a box for 3 10" L7's but I am completly lost on the size and position of the port(s). The box is 4.5' x 1.6' x 1' split into 3 chambers which have an ~ volume of 2.24'.

In kickers manual it says something about "2.25 cu ft + port; 3 x 11.5" 18" long". Im gusesing that means a port opening that would be 3 x 11.5" but dont I have to build something internally along with that slot and posotion it right?

As for the online calculators that give you dimensions for round ports sure it gives the diameter of the tube but how far do I know to stick it into the box as well as where to place it etc?