XRAY - Model racing cars

I'm going to do it the same way on my T2 as last year on my FK'05

That space is not big enough. If you like it lower you can cut your bumper and insert it in the bumper.
Xray had such a , but you can make it yourself.

I have mine like how Mario described

thanks to everybody for your suggestion, I don't like very much the idea to put it in the bumper because of the fact I don't have a personal transponder I found it not very confortable in removing it at the end of every run (you have also to remove the plastic plate at the top of the bumper) I've chek the balance (left /right) of the car and I've decided to buil a transponder holder to fix it at the righ front side of the batteries pack. I'll let you know how it works!