I'm designing a very, very low set of landscape stairs (really more like a wide stoop) to transition two areas of my yard. My plan is to pour a concrete base slab, build a core with CMUs on top of that, and then clad everything in natural limestone. I'd like to integrate low-voltage lighting under the tread noses.
My plan so far is to cut a network of grooves into the CMU core to run the low-voltage wires from the fixtures back to the transformer. The treads would then go on top, concealing the fixtures and wires. However if I mortar the treads in place, it will be very difficult to replace the fixtures when they inevitably fail. Could I get away with some kind of less permanent fastening, like a masonry caulk that could be cut away when the treads need to be removed? The stone treads are quite heavy, and are mostly held in place by their weight. I think I would only need something to keep them from rocking/budging.