If you want to mount it discreet, here are 2 suggestions:
1) Invest in and undercover antenna. If someone sees and antenna and they are looking for something to steal, they are going to be looking for a radio and will tear the vehicle up more looking for it.
2) Mount that head in the glovebox. In my area, the plainmarked units would mount there radios in that location.
Those are just 2 ideas too consider. Other than that looks good for what you have.
Or another idea would be to come up with a slide out panel that you could mount under your drivers seat and than pull it out to see when your drive if you wanted to see what was broadcasting. When your finished just slide it back under the seat when you arrive at your location.