Add extra pages to 'More Information' Sidebox

I just want to stress that I am a beginner, and the steps I took seemed logical, but don't seem to work.

I've used up the 3 pages that can be added to the 'More Information' Sidebox (define_page_2.php, define_page_3.php and define_page_4.php) but I want to add at least 2 more to the 'More Information' sidebox.

What I have done is copied the pages 'define_page_2.php' and 'page_2.php' etc and changed the numbers to 5 and 6 in the following folders. (I also changed the numbers within the pages to match):

includes>languages>english>
includes>languages>english>html_includes>
includes>languages>english>html_includes>classic>
includes>languages>cymraeg>
includes>languages>cymraeg>html_includes>
includes>languages>cymraeg>html_includes>classic>

Those are the only folders I can see a reference to these 'numbered' pages that appear in the 'More Information Sidebox'.

I've also added a reference to these 2 new pages, under the 'BOX_HEADING_MORE_INFORMATION' section of includes/languages/english.php and includes/languages/cymraeg.php .

I can see and edit the two new pages (define_page_5.php + define_page_6.php) under 'Stockroom>Tools>Define Pages Editor' but they are not listed in 'Stockroom>Configuration>Define Pages Status' and therefore I cannot switch them on so that they appear in the 'More Information' Box. Any ideas?

Should the above work, and if so what am I doing wrong. If the above is just plain stupid (and there is a good chance that it is!) can somone take me through the process (in an idiot's guide kind of a way) of adding extra pages to the 'More Information' Sideboxes? :lookaroun

I've recently been searching for a way to add links to the Information Sidebox. Here is something I've found that might give you some insight... i'm also a beginner and am not sure yet if this is useful but you could look it over and see if it gives you any ideas.

https://www.zen-cart.com/tutorials/index.php?article=230

Good luck!