Hi Dustin,
You will be able to use the same OAuth credentials that you use for AdWords API to make the API calls. You will need to enable your project to make Google Ads API calls by following the steps mentioned in
this guide. If you are requesting OAuth credentials from a manager account and are accessing a related customer account, you will need to set the
login-customer-id header to the customer ID of the manager account, removing any hyphens in the ID, Could you please take a look and let us know if you have any issues?
Thanks,
Bharani, Google Ads API Team

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