This is an useful example / addition from around 1963 of The Triang Transcontinental diesel headlight assy and the bracket to fit on the top of the motor unit all as per the photo and title. Bulb tested -.
Reproduction Steps For Tri-ang Triang R253 R353 Dock Shunter (Set of four)
Tri-ang Hornby R253 R353 Dock Authority Shunter - Motorised Bogie - Runner (#551
Hornby Triang R253 Red Dock Authority Diesel Shunter 00 gauge
Triang R253 OO Gauge Black Diesel Shunter 3 Industrial Locomotive Runner Unboxed
