webhooks v2 add to header?

I'm guessing the answer is no, because there is nothing in the documentation, but for giggles, is there a way to add to the webhook HTTP header that gets sent to the target URL?  The application at the target requires an "Authorization" header variable with a bearer token.  Unfortunately have no control of that requirement.  So any idea if there is a way to add a custom header variable when the webhook is defined or modified?  Thanks