Dont take my advice as the bible, i work for a builder, but personally i think i would make it more like 60-100mm from the edge, as sometimes with just decrative slabs the rio (steel) inside the slab might only be about 30mm from the edge. And you want to try and get the bolts on the side of some rio as it will reduce the chance of the edge of ya slab braking away. Just some advice mate.
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TJ = Tough Jeep
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