I've had 3 Favorits (broken 2 for parts) and all have suffered from corrosion where the body steel joins the rear wheel arch, on the horizontal surface directly above the wheel. When cutting up one of the Favorits I found that there is a passage through to this area from the recess where the rear seat belts attach to the body. An oil can filled with a mixture of new engine oil and Waxoyl (thin enough to allow it to run) squirted into this recess will make its way down to the wheel arch join and successfuly resist corrosion. Put some newspaper along side and to the back of the wheel to catch any surplus that runs out.

Yep they quite often rust away hidden underneath the little bit of plastic trim that covers it Good tip I'm sure this will help those that aren't too far gone.