Rear quarter panel windows on BX 19 TRI

[CitBXTRI]

Hi all,
I’m in the process of replacing the plastic windows in the c pillar section of my BX and wanting to know what’s the best way to remove the old silastic?

 

[DoubleChevron]

if its sikaflex/windscreen adhesive, try a cutter ... its like a piano wire you pull through.