Front wing fixing

As it is not considered to a structural part of the vehicle it can be fastened on with chewing gum and sticky tape if you chose to do so .

Spot welded by the sound of things baldrick. Sticky back plastic won't be good enough.

Your probably going to say I'm overthinking this but I've always thought that if something, a wing in this case, is welded (even with spot welds) it's because it needs to be. I know that on an automated assembly line it could be cheaper to use spot welds than self tappers or bolts but car makers do consider running costs and especially with a front wing repair costs will be far lower for a bolted on one than welded and this can affect the insurance group rating.

So what I've made a long job of saying is that if it's welded when new then repair it by welding. Don't forget even a wing must supply some strength to the strut top mountings if nothing else.

If it was prescribed area I would prob fail it as an inappropriate mod 

We are talking about a front outer wing?
How could the wing be described as a prescribed area? It is not structural, nor is it a supporting panel

Would you expect corrosion repair to be continuous weld or just plastic padding? 

If it came in with the wing missing I'm not sure how it would fail

I am not a structural engineer and so I am not in a position to decide if it is weakened or not

There are few, if any structural engineers on here glen. We have been taught enough in our various vehicle tech courses however to know that the structural strength in a modern vehicle is derived from the shaping of the panels since it certainly is not from the thickness of the metal used. Where the outer wing is welded on does that not provide a clue that the inner wing is not strong enough on it's own?