I would like to make a vented box similar to this with the top ledge on it. The pic attached is of my current box.

The front of the box is to the right. I'd like to make a ported box in the same shape with two ports each pointing out of the top directly through my open 6x8 speaker holes in the deck.

ok... do it

Go for it. No one here will hold you back.

Of course you can, it is just harder to "measure" the internal volume which is critical to the tuning.

Of course you can, it is just harder to "measure" the internal volume which is critical to the tuning.

nah.

just fill it up with powdered gold, dump it out and see how many millions, I mean cubes, it holds!

(p.s. break it down into smaller geometric shapes that you CAN calculate. shouldn't be too hard)