My 1977 M17 has a HawkEye depth finder installed by a previous owner. I'm not sure what exact model is installed, but it appears to be similar to the DepthTrax 2B currently shown on their website ( https://hawkeyeelectronics.com/collections/sailing/products/depthtrax-2b-boa...). The transducer is "glued" to the hull in the v-berth area. I finally got the boat out this weekend for my initial shake-down sail but the depth finder just showed 0 depth. The previous owner did not mention any issues with it. The info on that page states: Glue-In Installation is for NON-CORED hulls or aluminum hulls thinner than 1/8” ONLY. Glue-in mounting of the transducer is NOT suitable for all vessels. Does the M17 have a cored hull or should this finder just work? Thanks, Rob