Glasgow-born Alex Fergusson is one of the great invisible architects of British post-punk, a guitarist and songwriter who kept turning up at the precise moment history was being made, then stepping back into the wings. He co-founded Alternative TV with fanzine editor Mark Perry in 1977, writing Love Lies Limp and Action Time Vision before slipping away. He produced early singles for Orange Juice and artists on the Postcard Records label. He was the musical engine behind Psychic TV from their fou…