i have a "98 stingray (220sx) stingray with a 350 I/O mercruser (Bravo). with the boat out of the water, i filled the bilge up with water till it started coming out from what i think it is the exahust hole perhaps also known as y pipe. this hole is located on the right of the Transom outer plate as you are facing the drive. how difficult is it to fix this problem?