Does anyone recall how it was done at Watsonia?  The project was
similar, completed in 1979 it saw the line altered to go under Watsonia
road, with a new island platform for Watsonia station in the cutting,
then a long cutting carrying the line under Grimshaw Street.  At the
same time, the line was duplicated.  I must have travelled over it when
it was single line, but as I was only 4 years old when the grade
separated line was opened, I have no recollection of the single track.
Cheers,
CH. 
-- Craig Haber albatross@harnessnet.com.au Manufacturing Systems Engineer (almost) Web Page Designer, Harness Racing, Railways, and Essendon Football Club fanatic http://www.harnessnet.com.au/