The Derby RTC Lab5 set was used as a track recording vehicle. It was replaced by a research owned Class 150 unit. The Class 103 left Derby on the 12th Feb '91 for Mayer Parry at Snailwell. The 9X14 working also included Class 116 53063/119 and Class 104 53451/529.

Alfred Roberts states that after 50397/56160 were withdrawn from Chester on 17/2/71 they were warmarked for service as a 'Viaduct Inspection Saloon' but this was never completed and departmental numbers never carried. The vehicles were stored at Penzance, Plymouth, Harwich (only BR appearance of a Class 103 in East Anglia, and co-incidentially the only preserved East Anglian 103 appearance 20 years later, the same unit) and Old Oak Common. They were later preserved, arriving at Shackerstone on 19th July 1978.

Brian Cuttell adds: DB975228 (M56160) did actually carry its departmental number but M50397 never did carry its allocated number DB975137. I saw this two-car unit at Penzance Depot numbered as such on 31/7/72 & 9/8/73. M56160 was in use as a loco hauled coach at Shackerstone on 16/9/79 & I recorded M50397 in yellow livery (unrestored) on the same date. M50397 may have carried 'Universal Viaduct Inspection Unit No1' but this requires confirmation.