@calewis

You would indeed need to generate a new CSR and go through the process of submitting the CSR to your SSL provider, awaiting approval from the issuer and then copying the newly created files to your server. At the server level, unless you need to merge the provided files, the only thing that should be required is a copy & paste followed by a restart of the web server (Apache, NGINX, etc).

The expiration dates for certificates are hard-coded when the issuer generates your certificate, which is why this process is (currently) required.