By Mike Walters He was the last English manager to win the title and chief architect behind St George’s Park, the crown jewel of his road map to success. Howard Wilkinson is retiring this summer aged 80 after a lifetime as one of the most important – and unheralded – figures in English football. Sergeant Wilko won the last Football League Championship with Leeds United in 1992, before money replaced glory as the game’s prime currency, and for one night only he was England manager, as a caretaker, 25 years ago after Glenn Hoddle was sacked. For the last 33 years, he has been chairman of the Lea…