FWIW, I am not even going to try and install a radio or antenna in the smart. Gonna stick with the 1/4 wavelength antenna and the external speaker/mic on my HT. Not sure where to locate it to get the antenna vertical, though.
If you want to try and you want good performance, I think (aside from his spelling ;)) Fred is right about the ground plane.
Hello all Iv been using my old and I mean old VX5R HT with the rubber duckie it works pretty well. I drive an 09 passion with the vista roof. N6JOL Michael