Many thanks for the information tsc - I will make a note of your directions now and hope to get there. I still have the booklets 'Antiquities of West Cornwall - and how to get there without a car' from when I visited West Cornwall in the spring of 2010. Also - 'Cornwall' Archaeological Heritage', so hope I can get to some of the sites I missed back then. Mainly just chilling out though ....
Thanks Sanctuary, will definitely try for Zennor Quoit too, if it accessible by public transport and/or foot - have made a note.