Well after procrastinating about 2 weeks. I finally changed my Y-Arm belt last night. It took only about 10 minutes. I thought about finding out if there was a way to tune the belt tightness using a app. In the end the experiment did not work. The tightness of the belt is still determined by how hard you can pull the belt. There is a bit of deflection in the belt when you press down on the top. I did not measure that. I pulled the belt taught, then clamped the end to the belt using some forceps. Then tightened the Ty-rap as snug as I possibly could. Once I did that I re-calibrated the the hotend, Z-Probe, and Z-Probe offset. Everything worked fine.
What I did discover during the removal of the old belt, the two screws on the back of the Y-Arm had become loose and where loose enough to cause some slack in the Y-arm belt. This was most likely the cause of the sloppy prints I was starting to see. So if that seems like a place everyone should check out. If your prints become a bit whonking check the anchor screws that hold the belt in place on the back of the Y-Arm.