Firstly I'm not sure whether to post this here or the Cinnamon forum so apologies if it's in the wrong place.
Specs: Linux Mint 17 Cinnamon
What I'm trying to do basically is change certain application icons.
I have removed LibreOffice from my computer and replaced it with WPS office suite (or Kingsoft as it was known). They changed their icons a few versions ago but I like the old icons rather than the new ones.
I have changed the icons in the menu as per the screenshot below:

As you can see from the below image it doesn't change the icons of the applications once they're launched. I have changed the icons in /usr/share/applications and renamed the original ones to xxx(old) but that didn't work and for some reason it created an extra menu entry


I don't want to change the whole theme but just these 3 specific icons, can someone show me where the icons are located please?