This has been a great week for me, as it is half term in the college, so I have been able to spend 5 days from 9am 'til 4pm just working on my sculpture. The images above show the frame that holds the front halves together and how the piece looks from the front now.
This is the technique called 'cut and shut' (thanks Bob). This involves strapping the pieces together and running a grinder between the halves. After hours and hours of grinding it was possible to get the pieces together very tightly.