In order to show the values of each dial, there are two separate methods. One is using a valuebox which displays the number near the dial itself. The issue with value boxes and gauge charts is that the other dials can get in the way and block the display of the valueboxes. In general, the best way to display valueboxes on gauge charts is to use:
This will place the values at the tip of the dials. You can make it look nicer using padding and fontsize.
Furthermore, a second method is to display the values of the dials in the legend. You can decide which way you prefer, or use both!
Here is a demo showing both strategies employed: