There is another solution IF you want to retain the current exhaust.
The rub occurs because the axle moves sideways during cornering , you can minimise this by fitting a Panhard Rod. It is a bit overkill I agree , but may save you a 600 km trip.
Andy G 1999 +8 , Indigo Blue. Ex-John McKecknie/Mike Duncan 1955 +4 racer.