Their must be a reason for chewing in the horn with the woofers
Are you referencing the baffle geometry, with the two drivers snug against the horn? I'm reminded of JBL's Drew Daniels' plans for his home brewed speaker:
There are some tricks that are essential for eliminating horn "honk."
The first is to use the cone driver placed just below the horn, all the way up to a frequency where it begins to "beam" due to the relationship of sound wavelength and cone diameter. At a frequency where the resulting Q-factor (directivity) of the cone matches that of the horn, the transition from cone to horn will be smooth, and not abrupt-as it can be in systems where the cone is too large and the horn is too small. If this condition is met, and the frequency response of the cone is good well beyond the frequency up to which it is used (a well-behaved upper end rolloff), then the horn will enjoy a seamless transition from the cone and will not honk, assuming its frequency response is good and uniform over its output angle.
I experimented with a dozen midrange drivers before I was confident that the 2123H with its high efficiency and limited excursion linearity would produce sufficiently low distortion. It is a wonderfully transparent driver and a large part of the reason this speaker system sounds like listening to live music rather than loudspeakers.
The driver is mounted on the baffle as close to the horn as I could get it with my inexpensive mid chamber geometry. You could do better if you are willing to cut the shape of the mid driver's frame into the lower lip of the horn and snug the mid frame up into the cutout and, of course, figure out a mid chamber arrangement that would clear the horn and driver behind the baffle...