I do have the latest version now and it does appear. I had too many wikis' admin pages open at the same time when checking and missed it.
I'm going to use different templates as I can then put a link in the wiki to download each manual with a chosen template specified in the link.
Now a new problem : Images need to be bigger. I've got the images in media browser at a good enough resolution but they are scaled before putting them on the page. I've added
img{width:100%;}
to the template style.css but where the original image in the wiki has been entered as S, M or L this downsizes the image before passing it to PDF where its then expanded to fit the page width and looks horribly pixelated. I might just need to set them all to original size.
Unless someone can think of another way to achieve this?
The ultimate aim is to make all our manuals accessible to people with visual impairments.