Two of the round metal cowls which bolt on to the radiator and hold the fan in place were badly bent, so no good for re-fixing until they were round again.
I have made up a wooden "wheel", 285mm in diameter, with a flat cut to clear a flange welded for a mounting bolt.
I got two lengths of 6" x 3", glued them together to form a 12" x 3", drew a 285mm circle with a compass, and cut it mostly to shape with a bench circular saw. I then rounded it to shape with a belt sander.
I have pushed the cowl over the wooden wheel, and will tap it into shape with a hammer before repairing the rusted mountings for the radiator.
I hope it stays in the new round shape. This was the only way I could think of getting it back to its original shape.
If the "wheel" is cut slightly too small, just wind duct tape around until you get the right size.
Photos to follow next week.
Alex in Norfolk.