Just thought I would close this off with the final information. I managed to get hold of some 30×30 angle irong, 770mm long. This fitted perfectly, slides under the petrol tank straps and the spare wheel now fits as it did before.
The only thing that looks wrong is I took too much of the floor insulation away to fit the 40×40 angle iron, still, all is now finished.
Just for information, I didn’t have a trailer around to test the light fitting but I did have a set of magnetic lights, very easy to sit in the car and see the lights in front of you.