Thanks Luddite & Button. I've sorted out TM Image and amended this post.
The first image shows the alternator tight in the scalloped bodywork. The second image is the best view of the two mounting/pivot bolts. The bolts are both installed with the heads outermost. The back one I can remove as there is a slot in the inner wing to get a spanner in. The front one is considerably over length and even if I could undo it it is too long to withdraw forwards.
I think I've got 2 options, unbolt the mounting bracket from the block or cut a hole large enough to pass a socket in the inner wing. I can always fit a blind grommet afterwards.
![[Linked Image]](https://www.tm-img.com/images/2019/07/24/IMG_4956.jpg)
![[Linked Image]](https://www.tm-img.com/images/2019/07/24/IMG_4959f9004fec848b694d.jpg)