Some pictures (just because...)

The first picture shows the Infinity 122.7W (left) vs the Alpine Type R 12D2 (right). Most of the 122.7's "motor" is a heatsink for the neo magnet structure. The Type R's motor is totally enclosed by its aluminium basket. It's quite a bit deeper than the 122.7W, but that doesn't matter for my needs.

The second picture was taken partway through the installation process. The top part of the trim ring is missing from the 12D2 on the right. The enclosure is a fiberglass and wood box that fits into the spare tire well of my Tucson.