MGB281

I spent a day rolling sheep fleeces a long time ago and I can confirm the effects of lanolin on my hands. I tend to look at advertising with a lot of scepticism, their claim that the Lanoguard creeps under the rust as opposed to just encapsulating it is one that catches my eye. However it does have the advantage of being a natural product though. Whether your MG is a dry weather car only or a daily driver like ours there is a good reason to give your car a regular treatment with a cavity wax. As Ellisojo rightly states that fastening of the wheel arch liner is a mud trap, an annual coat of wax will help prevent any corrosion. We tend to forget that the "waxoil" add says that it "creeps" and during hot weather it can and does creep downwards on vertical surfaces which can lead to the drain holes in the sills blocking with wax.
One thing that always surprises me is that it's the offside front wing that rusts more than the nearside. Woolies have two rubber extrusions that might fit onto the wheel arch lip, one might hold the liner in place as intended, the other might just protect the lip of the arch from stone chips