Early next year, a 650 tonne crane will be assembled in the middle of the Stadium site to lift the 28m high lighting towers on to the inner ring of the cable net roof.
Then, in spring, the net will be covered with material to provide the correct conditions for the Games.
"We continue to make good progress across the project though there are still challenges ahead," said Olympic Delivery Authority chairman John Armitt.
"The next year will be our toughest as the number of workers increases and activity on the Olympic Park reaches its peak, so we cannot afford any complacency."
The Stadium, which will form the centrepiece of the 2012 Games, is due to be fully complete by the summer of 2011.
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