Dennis, I have been doing my measurements outside and windowing them for a while. The bass was measured on ground plane with the mic 4 feet away.
I'm still at the starting gate modifying these, but the Peerless XT25 will fit in the hole once you widen the cutout. I plan on using felt on the front to make up the depth difference, which will also help with diffraction.
That is about as far as I got, so I'll need to do driver in box measurements, and then a few rounds of ordering crossover parts to get anything usable. I'm backed up with reviews and real life so it will probably be a few weeks before I have anything new to share.