This is a finished concept that I doubt many will need but maybe it will inspire some problem solving for you?
I needed to push a button on the back of a network rack once every day. It is not super easy to get behind the rack...so the button pusher was born.
It uses a 36" flex cable pickup tool as the driving cable.
Parts were mounted using 3M VHB tape.
A nyloc nut, 2 washers and a bolt form the pivot. The flex cable is hot melt glued to the holding bracket.
Not very complicated but the concept was sound the geometry of the pusher was key.
I use it every day and it works well.