Antenna wire mounting depends on the period, and the radio fit. With the VHF radio, a whip antenna was used, just aft of the radio room top hatch. When a gun was not mounted - which it mostly wasn't on the later 'G', then the aperture in the hatch window was filled by either a piece of clear Perspex or a sheet of alloy. The LW radio had a wire antenna running from the 'wall' of the radio room to an anchor point on the port wing, an the SW radio, if fitted. had the wire from the mast to the fin.
there were variations of course, so best to try to find a pic of the actual aircraft.