Such sad news, though by now, not unexpected. Mo passed away this morning. There are many tributes to him on the web, with a fair number of those coming from internationally-respected musicians.
I'd known Mo for many years. I first saw him doing a week at a night-club in Liverpool with Hank and John Farrar back in 1974 and was later invited to attend one of his recording sessions in Oxford - probably twenty years ago - and met up with him most years at the Pipeline Convention and at various other venues. He was a wonderful, intuitive, player in any style and a great bloke to know.
Of course, as well as working with Cliff Richard (for instance, at the 1978 London Palladium reunion concerts), Mo was the Shadows' bassist on the now-legendary John Peel "Sounds On Sunday" sessions of late 1973.
R.I.P. Mo.