The pics attached are where I routed my wire for my Bluetooth microphone. The fist photo is where I started to prize the pillar housing from in order to see what I was doing.

I found that slowly slowly was best direction and a firm grip, supporting both the internal and outward facing parts of the material clad moulding !!

No A-pillar was harmed in this process.

I posted these as I though it (may help) others.