CB Antennae locations...

^ probably better to ask them directly:

https://www.benelec.com.au/

I still run a bracket which is stuck to the outside of the windscreen which runs an external aerial. You get the benefit of an externally mounted aerial mounted at roof height without being attached to any painted surface. No marks, no damage. You can get them for under $25. I need to find a better way of securing the coax, but I've been too lazy!