North or South Devon Roy?

What you need to look for is a small privately owned garage like this one that Aaron Calder discovered some years ago in Southampton.
https://spitfiregarage.co.uk/

Yes, too far from Devon but it'll give you an idea what to look for. Rally car specialists are top of the list as they are well used to welding metal in close proximity to aluminium panels. Also perhaps, coach builders.

Can we see a few photos of the areas you are concerned with. If you are having trouble up loading them then say so and we'll find a way around it.

Randa