Finally got around to measure the box dimensions.
Internally its 348mm wide at the rear, 467mm at the front and 928mm tall.
Calculated roughly 69L internally (I measured handles and bracing, 69L is left when I subtract these).
Four ports, 67mm in diameter, 70mm long.
Around 15L goes away for drivers (2x 12NDL76+TPL-200H.
Leaves me with 52L. I measured the box impedance with drivers using DATS, looks like it's tuned to 54hz right now.
I would like to raise this to around 70hz, the box has a pretty steep rolloff below 125hz measured full-range, I'm targeting a 80hz crossover.
[ATTACH]209419[/ATTACH]
