Dont you dare!
I would not epoxy the transducer anywhere. thats way to permanant and you seend to thing itwould be temporary. So try these ideas. Cut a piece of pvc pipe large enough for the transducer to fit into and silicone it to the hull inside preferably forward. If you place it very far forward it will not work well because of air getting to in from waves ect. but then if you put it to far aft. you will learn how deep it is after you find the rock. drop the transducer in the pipe and fill it with water. then seal a top on the pipe to keep the water in. If you want to remove it later you can pull it off the hull. If you want to get a little better go to a medical suppy house and get some of the conductive jell that is used for ultrasound techs. Its cheap, fill the tube with that and push the transducer down in the jell. the key is no bubbles of air! if you drill out a pvc pipe end and mount the transducer to it it will hold the transducer lever and hard against the bottom of the pipe, All this can be removed and reused or relocated if you dont like how it works.
