The car in question is not a Mercedes Benz. It is a Binz, one of the very rare, hand built, and often bespoke station wagon conversions carried out on Mercedes sedans during the 1950s and the 1960s.

John Green, who runs MB Spares and has a remarkable collection of the German company's creations, said this vehicle came into his life in February 2012.

"A guy walked in and said `I have a Binz [wagon]," he said.

John's immediate response was "yeah, sure" but he was soon convinced.

The car had been used by a Catholic sister and then sold on by a now defunct home for retired clergy in the Southern Highlands.

Despite numerous battle scars it was in surprisingly good condition and had very little rust.

John took the car on and embarked on the slow process of a total restoration which is now nearing completion.

Much that had raised questions, including the heavy-duty fittings supplied as part of option code 471, became clear when another MB Spares customer came across a newspaper clipping dated July 8, 1967, from page 16 of The Canberra Times.

The article made reference to the then Roman Catholic Bishop of the Kimberley, the Most Reverend John Jobst, who used "one of the only two Mercedes Benz diesel station wagons in Australia" to travel around his massive parish.

The article claimed the bishop did his own repairs and servicing and drove 75,000 miles [120,000km] a year. John, who has the car's log books, said both statements were mild exaggerations.

At the time the article was published the big wagon had covered 47,000 miles [75,200km]. While much of the service work was carried out by Western Australian Mercedes dealers, one entry had been signed off on by "J. Jobst".

"Never let the facts get in the way of a good story," John told Gang Gang. "Journalistic licence was alive and well even then."

The car, a 1966 Mercedes 200D, came with a four-speed column shift manual gearbox and ran a two-litre diesel.

Performance would have been stately rather than scintillating given even in sedan form the model was asking a modest two litre diesel to haul almost two tonnes of motor vehicle.

The 200D sedan maxxed out at just 130km/h and took 30 seconds to reach 100km/h.

The bishop, who ordered two of the big wagons for the Kimberley diocese, was probably influenced by a number of factors.

"He was Austrian," John said.

There was also the point that the cars were large, relatively comfortable compared to vehicles such as a Land Rover and very, very tough when fitted with option code 471. "This translates as `special export version for bad road conditions'."

Special modifications included bash plates under most of the vehicle to protect components such as the engine, gearbox and drive shaft and a false floor to carry two jerry cans of fuel and the spare tyre.

Bishop Jobst, who only died in 2014, would have been very familiar with the jerry cans which were so-named because they were first used by the German army in WWII.

He had been drafted into the Wehrmacht from the seminary as a medic, attached to a Panzer [tank] regiment and sent to the Russian front where he was wounded and sent back to Germany just in time to be captured by the Americans.

Bishop Jobst became the first Bishop of Broome and the Kimberley in 1959 and held the post until 1995.

Ordained in 1950 in Limburg, he was buried in Brennberg, Bavaria, in July 2014. The fate of the second Binz wagon is unknown.