I had a nearside stay crack in the same place and refitted it as Gomog suggested.
It makes sense as the amount of movement in wing, chassis and bracket has to take the strain somewhere.
Put a washer between the wing and bracket and contour the bracket should solve the problem.
My 1959 Morgan stay was too stiff and the top of the wing around the sidelight fractured.
Many early Morgans have plates welded in this area so movement on the top of the bracket is far better.
