Lorries were loaded in the North and informally waited at a nearby service station on the motorway to take up the buffer of traffic delays. Units were called onsite in the exact fixing sequence and were lifted up by mobile crane to four different gangs working simultaneously on separate parts of the site. Lorries delivered to ‘their’ gang at set intervals and were supported by a crane that lifted units into position and held them until fixed. Lorries for different gangs waited offsite until they could enter a single site access and be processed and driven to position. Gangs staggered their work to receive lorries at different start times and were trained to work to identical targets to maintain staggered deliveries.