Fiat 500 – Autoradio – AUX

Hello, in my Fiat 500 a relatively simple car radio is installed. I can listen to the radio and CD (also MP3 CDs). If I press the CD button, if there is no CD in it or a CD is running, it comes in the AUX display. From this I conclude that it is really possible with this radio to connect an external signal source, if you had an input for it. Questions with the dealer showed that there are equipments in the glove compartment a 3.5 mm jack socket Now my questions: – Who has a similar equipment and knows how to connect external signal sources? – How can you expand the radio, in order to possibly find a corresponding socket at the back of the radio, which you can then somehow put forward. I did not succeed in removing the front panel. Thank you very much for that! Greeting, Noepes – enthusiastic Fiat 500 driving PS: I had my 500er converted to gas drive – I am very contentious!