Weighing one ton, the BMW sculpture had to be lowered over Mr Marsh's grave by crane in an operation involving 20 people.
The detailed design includes silver-painted lights, a complete dashboard and tiny BMW logos on the wheels. It even has the personalised number-plate: 'Steve 1'.
Mr Marsh, who was known as 'BMW Steve' because of his love of the cars, died in his sleep last April. He had been suffering heart problems.
His wife Joanne, 51, and children Kerry, 31, and Vincent, 27, from Forest Gate, East London, drew up the designs for the headstone with the help of a stone mason.
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