[Brian]

Kevin, Thank you for your reply. Actually, I dunno what style LED's you tried in the 34, but the ones I run are the same size as the tail light lens, and fit directly behind the lens. They are bright directly behind and at an angle. Far better than a regular tail light bulb, even when fitted into a white painted housing....
Anyway, it's getting dark here, so I went out into the shed and am happy to say there is absolutely no glow emanating from the tail lights. Hopefully, now the light switch has dried out, the problem has gone! Fingers crossed. Thanks again, Brian