Jim Cullen built the car as a 500, initially using a JAP single, later various Nortons. It used a two-tube chassis with wishbone front suspension, swing axle rear, and Cullen's own alloy bodywork and cast alloy wheel centres. In the mid-'50s he hillclimbed the car, and raced it at Waimate, Oamaru and Wigram. Bill Ingle in Dunedin bought the car in 1962 less engine, modified it, and had some hillclimb and sprint successes with it. Many owners further down the line, in the late 1980s, Kevin Telford bought the car from Ted Giles, extensively rebuilt it and installed its present overhead-valve 1000cc Harley Davidson engine and gearbox. The car now also has new wheel centres, made by Phil Ingles from patterns made by Trevor Timms. Chris Cullen of Christchurch and his sister Denise Dymand, children of Jim Cullen, bought the car in the mid-'90s and since 1995 it has appeared in Classic events.
Thanks to Rob Young and Terry Wright.
If anyone has any more details or photos, please get in touch.