Hi @mkirkland
It may be worth it to take a look at the strapi-provider-upload-aws-s3 provider that we manage ourselves, as this currently is the only provider we natively support that also has a path option (sent with the upload request):
As for modification you are correct that you should fork the package and you can drop it in the ./plugins folder (will need to create this folder if you don’t have one), or you can push it into GitHub and use the GitHub packages / NPM to release a modified version.
Alternatively the original author of that provider is quite active in the community and is very open to pull requests, you may want to talk with her @Lith
The repo for that provider is located here: GitHub - Lith/strapi-provider-upload-google-cloud-storage: Google Cloud Storage Upload Provider for Strapi