As a minimum, you will need to add at the beginning of the 3D Script:
RotX 180 ! to rotate the window around the X axis
AddY -B ! to move the window up its height
AddZ -WALL_THICKNESS ! to move the window back into the wall the wall depth (old school C_)
This assumes no Del Top statements, which would delete these commands so they would need to be repeated after the Del Top. The Script could be more complicated and these commands could need modification, depending on the exact 3D Script, this may call for a bit of trail & error to fix all the code.
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