HomeWizard Sensus 620 adapter (R400/R315)

Print the adapter and use the 2 smallest enclosed screws from the HomeWizard watermeter to mount it. 
You have some room to align it well. I found it the easiest to let some water run so the meter is spinning. Then it's quite easy to align the adapter in the middle of the wheel.
Then tighten the screws (don't overtighten) until the plate doesn't move anymore and install you HomeWizard and calibrate it in the app.