W1
Large Cattle Wagon (MEX).
Use the Association BR Cattle Wagon kit (plastic), replace top doors with those from the 11'6" DC chassis etch, lower and flatten the roof, and replace the diagonal end straps with flat X-strapping.
Alternatively a 3-D printed body is available from Ian Smith.
Prototype
Over 1200 built 1888-1904.
Some (at least 100) were reclassified as V30 "ALE" wagons, in 1939, for carriage of Guinness.