Ya dun good, pilgrim! Those plans are easily available and it is a precise, but not difficult project. I did the same thing with one twist. A sometimes limitation of the Thiele cabs is they are so small (but HEAVY) that they may not work well if you want to use a single one with a longer head. (Use two-----400 watts power handling!) So, I built one to the exact specs. The second one has longer sides so it WILL hold a "normal" head when it sits horizontally.....The interior is exactly the same, so the critical sound shaping design is intact. In essence, it just has a "wing" that adds some physical dimension. So, I have the flexibility of using 1 cab or two, though they are mismatched, size-wise. If I was doing it over, I would probably make them both in the larger size.....For MY purposes. In your case, a stereo setup, it sounds like the two matching cabs meets your needs perfectly. Great work!