I know this doesn't answer your question, but the sensitivity of a radar detector and particularly a laser detector is a function of the height of the detector above the road surface. That's why Valentine has never offered a behind-the-grill setup. I've tried building a behind-the-grill remote some years ago, specifically by sealing the main unit in a lucite box, the sensitivity was notably poorer, probably both because of the relatively low location and because the thin chrome plating on the grill deflects a lot of the radar. Anyway, I abandoned this after just a little while.

I currently have a Valentine-1 with the remote display. I have my main unit in the pocket of a visor organizer ($5, Target Stores) on the passenger's visor, with a window cut out in the leading edge for laser reception. The cord is run down the "A" pillar, under the glovebox and into the console, appearing through the leading edge of the shift boot. I have the remote display plugged into the cigarette lighter, it doubles as a "kill switch".

I have a similar setup in my Porsche except it's hard wired into the radio harness and the display is inside the center console. I have had a couple of actual "saves" on laser ("everybody" says you're already dead when the detector goes off on laser, that's not completely true) but the margin of error is sooooo close for laser that I feel I need every microsecond I can get.

The setup is completely invisible from the outside of both cars.

-Punsxutawney Phil