Scania cb aerial

Can anyone tell me where the cb aerial wire runs to on a semi high roof .I know that the mount on the left hand side takes the aerial I just don’t know where the wire runs to I even asked at scania when it went for service and they didn’t know .Ive had a look inside the overhead compartment with a torch but can’t see owt but don’t want to take it down and disturb tacho so would appreciate if someone could point me in the right direction Thanks in advance sorry if I’ve put it in the wrong section (newbie)