I just rigged up a mount so I can use my V1 in my Miata. I know it's kind of vehicle-specific but hopefully it gives someone inspiration for their own install.
Here's the story of how and why... There's pictures below, but this should answer any questions about why things are there.
A couple years ago I went to install my Bel 955 in the car (my first hardwire job!). I wanted it above the mirror, but the mirror was suspended from the windshield frame so there was no room. I removed the stock mirror and put in an AutoZone replacement that glues to the glass (I actually just removed this so I could reposition it, which is why it's not in the pictures.) I could then position the 955 between the mirror and the frame, so I was happy.
Anyway, last year I got tired of seeing the gaping hole in the trim so I cut out a little aluminum strip and painted it black to fill it in. I drilled two holes so it could hang by the factory screws for the mirror. I also drilled a hole to run the hardwire cord through.
I had the 955 mounted with a custom mount I made that doesn't use suction cups. The details are here - Custom mount
From the outside, that mount (and the suction cup mount that preceded it) are ridiculously obvious. That's not a good thing for a car that accepts a pocket knife in the roof as a key. It worked out though, because I had a parking sticker covering it. I don't need the sticker anymore, so I decided to figure out how to mount my V1.
I didn't want to use the suction cup mount because I don't want suction cups showing on the windshield. My solution was simple: I drilled and tapped three holes for #10 machine screws into the aluminum piece that I used to fill in the mirror hole. Two of them hold the mount tight against the metal through the suction cup holes, and the third pushes down on the front to keep it level and tight against the other screws. I swear it's rock solid; it doesn't move at all and I think the plastic mount would break before it comes loose. The front screw is adjustable so the detector can be leveled.
Unfortunately, the V1 in this position is a little more noticeable from the rear than the 955 was.
I think that's OK, because I'm more worried about thieves than the police. The V1 comes down in a hurry more easily than the 955 anyway. The good news is that the mount is not as visible from the front, which is all you'd see with the top up...
The white crap on the windshield is from my old parking pass. The white strips are the dual lock that hold up the 955 mount. I'm going to be taking that off now that I have the V1 up. You can barely see the V1 mount to the left of that, which is pretty much the point of this exercise. That picture is from about four feet off the ground too, so it's invisible to a normal adult.