This may sound silly but try painting the bottom of the bars in the down unlocked position so that when raised to the locked position the paint becomes visable. Using hi visability paint like flouresent orange should do the trick. Reflective tape can also be used and it wont wear off like the paint.
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Best regards; The Home Smithy.
Your very welcome John.
Please let us know if you have any other concerns regarding this subject.
Best regards; The Home Smithy