If you scroll to the bottom of this forum, you should see a "Contact Us" link. But I suspect Bill will see your thread and respond to you in it.
If neither of those work, this is a link to their webpage:
https://gopowerhungry.com/
Bill is a great guy, who will not try to sell you anything you don't need or want. I've known him for many years now, and highly recommend his services.
- Jack