
I modified this slightly to suit my own thoughts on it.
Another very very nice man (AtomX) donated me a spare NA bootlid so I could hack it about to make a proper plug. Lots of fannying about and I ended up with this outer mould

A lot more fannying and I had this inner mould

The black flange around the edge is there to bolt up so that the two parts align properly

The lower part has this additional box section to add some strength to the structure

I added some structure to the frame and it fits on OK

I just need to make some hinges but my engineer friend who was going to help has a few problems of his own so its all down to me. Will pull my finger out when I get back off holiday.