Disconnect between deprecated Services and new Webhook leaving some of us high and dry

My older repos have a service link in the settings to allow us to set up Pivotal Tracker with a Token and everything comes to life for our automation. However, there is a disconnect as to how this can be achieved using webhooks. All of the details are hidden in a service that we don't know how to replicate in a web hook for newer repos that no longer have the services link in the settings. What is the solution for us to be able to bridge the gap for Pivotal Tracker between the deprecated services and the new webhooks so that all of us can continue to use our automation with Pivotal Tracker with newer repos, please?