I recently got a new Trek Verve+ 2 e-bike and have been enjoying riding it everywhere. I just added the Kiox 500 display and learned of the custom stem cover which replaces the original cover, and obviates the need for the handlebar clamp that came with the Kiox 500.
The new stem cover uses the existing holder, which can be detached from the clamp mount and affixed to the new custom mount. The existing holder is inset into the new CPT Stem cover so that the surface of the holder protrudes slightly above the rim of the new stem cover. This allows for the Kiox 500 to be attached or removed easily, just as with the clamp mount.
TIP: the original SIM cover had a smooth surface that did not allow water to get in underneath and onto the stem. The new custom mount has openings below it through which water could enter and sit on top of the stem screw. I add some clear silicone caulking all around the rim before installing the holder to keep water out. I also dropped in an AirTag, too!