I was wondering how to read this guide. Is the angle on the top representing what it looks like when you stretch thumb out? If tore ligaments in throwing thumb so I'll take a pic but think maybe I'm in tight category and need forward pitch a bit and thumb away from palm???

With your hand as it is in the picture put some pressure on your thumb pushing it toward your wrist.  Where you meet resistance is the angle you use.  Based on the picture I would estimate you'll get to about 90 degrees with some pressure.  Keep in mind it's all a guide for a starting point.

Shape and flexibility of the thumb joint, width of palm