Originally Posted by Army

I think that all repairs to problems like this should be welded. But that's my personal opinion and that doesn't count! You need to check locally what the rules are.

Fibre glass tends to be a big no no (for rust repairs in "structural" areas - and this can vary from country to country) in the parts of Europe that I know of. I was recently informed that in Germany they no longer accept butt welded joints (such is the TUV's confidence in people with MIG welders!) and you now have to make neat lap joint welds that are welded on both sides. That's not the case in Holland (yet).

So in short I think you need to comply with your local rules and regulations.