Fuck. That looks really nice. One of these days, I'll have to actually put the sensor in the pipe and connect it to the box. I might install mine the same way you did, but I've been debating whether or not to remove the radio from the car completely. Hmmm... Perhaps I could something like yours, and just lay a piece of tinted lexan across it so you couldn't see it when it was off...

EDIT:
Yes. I am lazy.
Yes. I am jealous.