There's a signal already in place but unlikely to be from when the line was in operation
https://www.google.co.uk/maps/@51.6409222,-8.7606741,3a,75y,57.13h,73.55t/data=!3m6!1e1!3m4!1sBw8bxi7Bvv1rKws-0E8LFQ!2e0!7i16384!8i8192
Just need to win the Euro Lottery to finance the job.