Can I Install w/o affecting database?

I am taking up the work on a new clients' open cart install. Previous programmer made all kinds of modifications. My question is so that I might reset all the programming to original install, can I run the install scripts and not have it affect the database? Or is there another way to get rid of custom updates done 5 years ago? oc 3.0.2.0. I am not wanting to upgrade versions, just end up with a plain vanilla install of 3020 but preserve all of the data.

Thanks for the assist.

You could use the Export/Import tool to back up your product data, then do a fresh install, and re-import the data.

thank you for the suggestion.