5: Flippered fish fancier
16: 'Trick or treat' reward, often
17: Whistle-blowers, of a sort
27: Hazarding a guess: doctor who puts stomach muscles in pulleys?
38: Overused, as a phrase
40: Masher's comeuppance, maybe
41: Fall off, as the tide
63: Word before crust or hand
68: Information from Deep Throat