These historic maps were in use from 1974 until December 2011. The relevant map number can be found by referring to the Index map for plotting sheets, listed below.
The planning application site was entered onto the sheet along with the application number.
To view an application site and number, find the correct map number from the index map, download it and zoom into the PDF until you can read the application numbers for the relevant property.
Once you have found the application number, you can view the full application by entering the number into the search tool which can be found by following any links to Search for and track planning applications online, which are on the homepage and many pages within the Planning section of the website.