Max 3D widget Size

I have a tower defense game Im working on and I have tower platforms I want to have a 3d Widget on and set to screen space. but I want it to keep its size when close but get smaller as the player moves away from it. Else if there are many platforms for towers and the player gets farther away from them the widgets will start to overlap.

I would like for the widgets to be in screen space rather than world space because screen space is easier to see when farther away.

A good example of what I’m trying to achieve would be something similar to the billboard components

Just make them smaller based of there distance to camera