On 23/07/2018 15:07, Harry Bloomfield wrote:
The usual way to get the windows out, is to use an electric saw to feel
for and cut through the bolts, once cut, the entire window comes out in
one piece.

Are you mad ?.

remove the glass and just unscrew the frame anchors or fischer
fixings. If frame anchors were used they can usually be removed
with a pair of needle-nosed pliers once the screw is removed.