path 249 or 250 include a series of elongate plates mounted on either side of track path 248 as shown in fig1 three elongate and arcuate guide plates 255 256 and 257 are fixedly attached such as by welding to the underside of the top plate 240 proximate and left of track path 248 guide plates 255 257 are evenly horizontally spaced to provide channels 259 and 260 three elongate arcuate guide plates 262 263 and 264 are similarly attached to the underside of top plate section 240 right of track path 248 to provide channels 266 and 267 the ends of the guide plates are pointed to aid in routing diverter blades into the appropriate channel or space as described further below referring to fig1 in conjunction with the height of the diverter blades of the side diverters of the trolleys each of guide plates 255 257 and 262 264 are made sufficiently tall so as to project down from the top plate to a height at least slightly below the tops of the upstanding blades of the side diverter elements of the trailing trolleys as so configured the diverter blades must either enter one of the channels 259 260 266 and 267 or enter the spaces laterally outward of guide plates 255 and 264 when the trolleys pass along track path 248 specifically when the trailing trolleys shown in fig6 and 11 are separately routed through track path 248 in a wall stacking direction diverter blade 139 passes along the outer side of guide plate 264.