Install live-chat app on 4 websites

General information for the website: TBA Description of requirements/features: I have 4 WordPress websites which I require a live-chat app/code installed into the footer of each. I will also require the removal of the previous brand of live-chat which i have trialled and no longer wish to keep. he job includes... 1) Remove old version of live-chat from all 4 websites 2) Add new live-chat coding to all 4 websites 3) Ensure live-chat is functioning correctly on all 4 websites, This is a fats 30 minute job if you know what you are doing. No 1st timers please. Immediate start! Extra notes: