Server-side tagging is all about control. Being able to intercept, modify, and even block requests as they come in before they are dispatched to their actual endpoints is extremely valuable.
The built-in Google Analytics 4 tag template has options for modifying event parameters and user properties in the Google Analytics 4 request, but did you know you can use these options to modify some of the fields as well, such as Client ID, User ID, and event Engagement Time?
![](https://www.simoahava.com/images/2023/03/override-ga4-fields-in-server-side-gtm.jpg)