tune 1 hz lower than you want cuz it doesn't factor in sub disp. idk but like .75-1 cubes at like 38 hz sounds good. depends on what music you listen too. try to give it 12-16" of port area.
And the meaning for the port being outside the box is becuase there is no room for it inside. If i placed it inside it would gice the 8 to much air space and would not perform correctly. It may have looked funny but it beat HARD