Dave W, What a kind offer ! - worthy of a true mudcatter. The flight is from Glasgow to Amsterdam and then to Boston so it makes it kind of ackward to get to Manchester. Very much appreciated nevertheless.
I'm now coming round to the view that I might pack the guitar, especially the neck and head with bubble wrap in the old fibre case and take my chances. My "proper" guitar is a Takamine and that's staying firmly on the croft.
The guitar that I'm taking is an old Yamaha FG-345 which has done ok over the years but not absolutely cherished.
Tell you what guys, I'll keep you posted of my progress and give appropriate credit or derision where it's due. KLM is the operator so the challenge goes out!
I've just remembered that this very same guitar survived honourably on a return LOT flight to Poland about 16 years ago.
Are the Dutch as careful as the Poles? In my day job I often worked on both Dutch and Polish fishing boats. I wouldn't like to guess!

Thanks youse all

Andy