Installing 2017 after 2018

Why? The usual reason - some clients are not on 2018 and I'm new here and only have 2018. If I install 2017 after I already installed 2018, will I have to do a repair install of 2018 afterwards? Just wondering if there are any pitfalls I should be aware of. And yes, this is a license that goes back several versions.

SolidworksAdministration