Thanks to all your ideas, I bought an all metal ball mount from Amazon. Its the peel and stick kind, supporting over 6.5lbs and is a SUPER strong magnetic mount.
Comes with a couple of metal plates to install on your phone. I chose the smallest one and stuck it at the bottom of my case. Because it's so small, the wireless charger in my car still works perfect!
Now, will it hold up in the AZ heat? I'll let you know if it fails this summer...