I must thank you all for helping me with the details of how to "adjust" the lock tumblers on both the bonnet (trunk) and glove box.
They now both lock (and unlock!).
Cheers, David

David:

Good news! Tell us how you went about it.

Hi Harry
Many of the messages I followed were by you, enquiring about getting the very small setscrew out to release the lock for the bonnet (trunk) release.
Obviously, the lock for the GloveBox is easier to access.
In both cases, I just followed more advice on this (brilliant) site to remove the tumblers and file them to match my keys.
I still don't know why my three keys, all identical & all "master" keys wouldn't work these locks. I don't suppose they both had been changed, perhaps wear on the keys?