Integrate an AWS RDS Database with Your Velo Site

Hi folks!
Can I have some additional clarity on configuring permissions when integrating an AWS RDS db? Specifically, within my AWS Secrets Manager, can you provide a clearer example of a Key and a clearer example of a stringified Value when doing permissions? And what, if anything, should be done to modify the Configuration settings inside of the App Runner? I have not been able to get Permissions to work, and it seems as if it should be simple.

Thanks!
Nick