Hi tlarkinjr,
I just picked up a 1979 176 Family Fisherman myself in march. My transom and hull is in good shape well from what I can tell.When I put the transducer on my transom was dry and solid. That said any water and moisture that gets in takes a long time to get out of mine. The floor/deck and all is sealed up a little to well on mine, no way for evaporation. As the temp goes up due hits the underside of the deck then goes back down. So I open the deck plate over the fuel send unit,and the one on the transom. Helps alot and the dripping stops in a day or two after a trip out. Hope this helps.
Jim