I do indeed have the photograph but it dates from 18 September 1981. The unit number on the leading vehicle is believed to be 126 413 which would make it SC51043, the DMBS now preserved at Bo'ness. Class 126 unit formations were very variable so there is no way of identifying the other two cars in the photograph. Unfortunately I can't post it here for copyright reasons.
Great photos Bruce. The unit passing Falkland Yard shows the typical list to the compartment side of the trailer car and as usual there is no unit number on the DMS. These were usually left off because of the highly variable formations and the unit numbers went with the DMBSs only. From the headcode 2B28 the Bo'ness picture dates from 28 September 2008, Day 2 of the Diesel Gala.
Keep 'em coming!