Ok, like Lynne said, not that simple so this might just be a "Meorazhar" original
Try this link -->
https://vborg.vbsupport.ru/showthread.php?t=170912, you can see how they did it via the code

Now perhaps you can use snippets to create what you want, editing postbit etc to show the contents of the custom field.
There are already many mods out w/ code snippets you could utilize for this, it just depends on your determination and ability to follow through until you get exactly what you want from it all.
S-MAN