I would do this.Chop the steel at the four corners, wherever it is easily accessible, taking the weight on the rope, then lower the released steel to the ground. Then you have a choice of either cutting the four stubs in the corners, still left in the wall, flush
These security bars are cemented into the motor / bricks.
How best to remove them?
Looks like a 10mm deep or less cut would remove ?As above. Use an angle grinder with a thin Inox blade. I am a weakling so I would make several cuts to reduce the weight.
Unfortunately, a 115mm angle grinder will only cut to a depth of 24-30mm but as the blade wears down, so will the depth of cut.
The horizontals look to be about 40mm deep. You might need a 9" grinder. Alternatively, I think a reciprocating saw might be safer
In your case, if you're careful then any accidental contact between the grinder and the wall might be with the mortar rather than the brick, which you should be able to patch up afterwards.
In any case, take your time.
(I wonder how deep they go?)
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