Chopping it down is lame.
Best bet is measure up and post in the Barefaced forum, where people will tell you to use two Eminence 3015 speakers (non-LF) and work out the porting appropriate to the internal volume. I'd spray a pair of round patches black to cover the other holes and have a round port in the middle, so they look kind of like a speaker through the cloth. Ideally, you want the two drivers on one side, for best sound, but that will balance and look weird. Not such an issue as those drivers are very light.
There is loads of other stuff to make a better cabinet, like lining the inside with knobbly foam and suchlike.