Granite Counter Top ? The norm is that the counter/cabinets have a finished
top of plywood (ours was 3/4") and the granite is placed on that after a
liberal application of silicone in several good sized 'blobs' across the
whole surface.
Our 3/4" granite had the edge built up so that the reveal on the sided/ends
was 1 1/2" and that overhang covers over the edge of the plywood 'underlay'-
No drilling, screwing etc

Thinking of buying a 1/2" granite capable drill bite, boring partially
into underside of
granite, then use epoxy to glue a barrle nut which I could then bolt into
from below.