Get rid of the knob on the bolt thrower and use the wire bent to 90 degrees for the handle, use some nice soft rubber tube or plastic compressed air line to make it more comfortable if the wire guage is small.
If you get a large radius on the wire bend it will be less likely to distort during use as for the knob on the lifter i prefer to make it from aluminium for better feedback with a minimum diameter of 1.5 inches for the yanks and about 38.1 mm for the rest of the world
Try to make the bits for the bolt thrower from old forged pipe keys by inserting the wire down the pipe and silver soldering in place leaving the shank as long as you can and the bit for the bolt thrower narrower than the locks bolt so it doesnt interfere with the bottom lever.
If the wire is a large enough guage then you can file a small flat area behind the knob and paint it white to draw some marks for the positions of the levers.
Also fitting a collar behind the knob to limit its travel to the range of the lever pack makes it bit easier to pick or decode