early on the previous morning , a vast team of men , each identically dressed in white , full-length boiler suits and dark blue hard hats , had disembarked from a cavalcade of similarly liveried lorries , and had proceeded , during the course of the day , to construct both a towering , many-tiered grandstand and an equally tall stage and platform alongside an area of lakeside which had previously been cordoned off to the gathering masses .