Correct, given a 'set' code of EH230 (EH = Eastleigh, where IIRC it was based for maintenance reasons) when operating on a boat train service, in the early days of (planning) computerisation. Although this set was the main 'go to' set for Boat train workings to/from Southampton (70s/80's), Mk 1 sets did also have a big impact on boat train workings to/from Southampton Docks, in the form of '8 Set H' or '8 Set J'. These were always referred to as '8 Set H' in the base plan CWN's, and were the sets that were known for their work on the Oxted road, but internally (at Clapham) we had access to two set's of each, but have never seen any evidence of '8 Set J' in any official documents that have survived to this day!
But they were issued as such on STP ACWN's back then, and often ran in conjunction with the Mk2 set when both QE2 and Canberra were in Dock simultaneously.
Getting back to the OPs comment about liveries, as I understand the SR vehicles were all in BR(S) green initially, although all those remaining were B/G by the time I worked with/diagrammed them (mid 70's). Some of those I was familiar with 50 years ago on the job are still around in preservation, which is nice to see!