Script to auto-color this map object?

So rp_evocity_v33x is a great map for a larger map, however this map was uploaded with some funky skybox as all white, not sure why.

Basically this box just outside the map is colored white, if I get the color tool and set transparency to max then we can see the skybox.

I want to know how I can make this color auto-set on map start so I don’t have to keep no clipping out to do it.

Any options I can use?