No Holes
We had a 1979 H-30 and if I remember correctly the transduce was mounted just forward of the water tank on the port side. It was mounted in its own separate well, which used the water in the well to couple the sound thru the hull and into he water underneath the hull. It worked quite well for shallow depths, anywhere on the Chesapeake Bay. For very deep waters, the coupling isn't good enuf, but my main interest was in knowing where the shallow water was. The nice feature was no thru hull holes required. Good Luck.
