Radio Aerial for Nuevo 2004

Hi. The radio aerial on our 2004 Nuevo (with overcall bed) needs replacing, I also think the cable is U/S.

Any ideas on where to fit a replacement aerial - mainly wiring accessibility
Or anyone know where the existing aerial, cable runs and how to access it. 

Looking behind the radio, a cloth wrapped cable disappears into the back of the dash and seems untraceable.

Need to repair before heading to Croatia next month.

Any (polite) advice welcome