Yes, I have the drivers forward and the PR on the back. It is just Danny's example box doubled with a single shared wall. I need to get some pictures of the new box up and get rid of those old ones with the PE vinyl wrap.
I'm not really a good resource for alternative box designs though. I've got a copy of bassbox lite, but in the end I had enough questions about box design, that I just played it safe and used his design.
I've seen a couple of other box designs on this forum. If you are talking about two stacked cubes with the driver and PR at 90degrees to each other than I know several people have done that. Actually all of the pictures Al at RAW used in your screw thread are that design.