The ninety-three WGS class wagons were all WGX converted for Superphosphate traffic. The conversions took place in 1969 and 1970 although 5 wagons reverted to WGX in 1970. Five were converted to WGN in 1975 but apart from three reclassified WGG in 1980 all of the rest became WOAX by 1981.

1969	WGX 33007, 33009, 33012, 33013, 33014, 33018, 33022, 33024, 33030, 33034, 33038, 33040, 33041, 33043, 33047, 33057, 33061, 33062, 33063, 33064, 33065, 33068, 33070, 33071, 33073, 33074, 33077, 33082, 33084, 33085, 33091 to WGS
1970	WGX 33001, 33002, 33003, 33004, 33005, 33006, 33008, 33010, 33011, 33016, 33017, 33020, 33021, 33025, 33026, 33027, 33028, 33029, 33031, 33032, 33033, 33035, 33036, 33037, 33039, 33042, 33044, 33045, 33046, 33048, 33049, 33051, 33052, 33053, 33055, 33056, 33058, 33059, 33060, 33066, 33067, 33069, 33072, 33075, 33076, 33078, 33079, 33081, 33083, 33086, 33087, 33088, 33089, 33090, 33092, 33093, 33094, 33095, 33096, 33097, 33098, 33099 to WGS WGS 33007, 33027, 33051, 33065, 33091 to WGX
1975	WGS 33022, 33047, 33052, 33077, 33099 to WGN
1979	WGS 33001, 33004, 33005, 33008, 33013, 33018, 33028, 33029, 33038, 33039, 33043, 33045, 33055, 33056, 33058, 33064, 33069, 33081, 33085, 33086, 33088, 33089, 33097, 33098 to WOAX
1980	WGS 33002, 33003, 33006, 33010, 33011, 33012, 33014, 33016, 33017, 33020, 33024, 33025, 33026, 33030, 33031, 33033, 33036, 33037, 33041, 33042, 33044, 33046, 33049, 33053, 33057, 33060, 33061, 33062, 33063, 33066, 33067, 33068, 33070, 33071, 33072, 33073, 33074, 33075, 33076, 33078, 33079, 33083, 33087, 33090, 33092, 33093, 33094, 33095, 33096 to WOAX WGS 33021, 33048, 33084, to WGG
1981	WGS 33009, 33032, 33034, 33035, 33040, 33059, 33082, to WOAX

WGS Diagram