I was lucky enough to be on the staff of 2GC. A trawl through my ancient logbook reveals these serial numbers in the 1960 entries: Mk 3s - WT895, 911 and 919, WV925, XA312, XE780, 790, 797, and 803, XN194 and 195. Sedberghs - WB921, 923, 942, 948, 962, and 976, WG497, XN147, 186, 187 and 189.