SR 2WIM EMU
Trailer 3rd
The LBSCR introduced EMUs using overhead power, but when the Southern Railway took control, they syandardised on 3rd rail, so the LBSCR units were converted in 1929to 3rd rail EMUs. .
Pairs of end cars were put in sets , each end having the original lower roof, making them very different to other EMUs on the railway. Designated 2SL, they spent most of their life on the South London lines.
The original first class trailer coaches were converted into motor and trailer pairs, similar, but no lower roof. These were designated 2WIM, and ran on the Croydon to Wimbledon line.
They lasted till the mid 50s.
Requires chassis, bogies, wheels etc and finishing.
Scale OO (1/76 4mm/ft)
more info about the 2WIM here
https://en.wikipedia.org/wiki/SR_Class_2Wim
more 3d printed models from Recreation21 here
http://www.rue-d-etropal.com/3D-printing/3d_printed_designs.htm