Lee

Well, if i change my reading settings, post page to one of the child pages i need highlighted, e.g blog, when i click into a single post in the blog page, it adds the current_page_item class inside the single.php template, but it only works for that one page, so, if it can do it that way, one can only hope that there is another method that targets all the pages rather than the one that i manually select

To answer my own question, for others who may want to do the same thing, I used a custom post type named gallery and included the tags taxonomy and used a custom taxonomy to add the years filter functionality. all works a treat!