Eastern Counties RL 687, DRX631K, Bristol RELL6G / ECW B49F. Ex-Alder Valley in 1981, new to them in July 1972 as fleet number 492.
Unusually for the period, painted all over red with non standard maroon wheels after a period out of use.
DRX631K has been preserved.

Photo taken by Eric Thompson, Summer 1985, Ipswich