I went with the Cobra 75 because I didn't want some big box around the Jeep!! Just not enough room. Under the glove box there is a small plastic panel that is easily removed, I mounted my stuff to the metal bar inside there and punched a hole in the small plastic panel for the connection. It is also easy to remove the glove box to make it extra easy to install everything.
Then I bought the custom antenna from cool tech that mounts in the back license plate.