One head on the front, one on the rear. The 911 is a very stealthy car because of the black color in this case, lack of chrome bits, very sloped/angled rear and front ends, and small surface area. Most reflective area therefore being the plates, and thats were the transponders are located.
Some of the pics were done with the phone's camera so sorry for the quality. I have played with the ilumination and shadow settings to bring out better de transponder heads since they are very well camouflaged black on black in real life.
Front is simply under flush under the plate. Not very visible anyway since its a very low car and same color as transponder lens.
Rear install is a bit more customised. The transponder head is right over the plate, integrated in a customed metallic lip, therefore giving the apearance of a stock part of the car, sort of anyway. The transponder is flush level with the bumper and the custom lip, so it doesn't stick out the back and doesn't stand out, but with a clear view of any rear overhead shots.
Interior harness was fitten inside the ashtray of the center console, each item (led, piezo, mute, and swithc) fitted into a custom black plate. When the ashtray door is close, everything is concealed.
Wider view of the ashtray inside the cabin
And a couple of pics of the car its installed on
And this is a picture of the car taken by the police (Photo-Lidar: LTI 20-20 Marksman coupled with digital camera) BEFORE the LPP. No more such pics since :twisted: