Wrecks and Relics, 4th edition. August 1974.
XN638 ex. 6.FTS SOC 18th December 1969. To Church Fenton dump.
XP632 ex. CAW SOC 8th May 1972. To Church Fenton dump.
XR680 ex. CFS SOC 8th May 1972. To Church Fenton dump.
As the date quoted is 1971, it looks more likely to be XN638.
Ciarain.