Mine originally had a proper fitting and all the messing around filling with glycol etc but the fitting was stuck on wrong when the boat was built and the sounder didn't give a reading half the time as it was pointing out to the side.
I got another fitting, but there wasn't space to stick it onto the hull as I couldn't get the old one off. Somebody on here suggested I just put it on with silicone sealant, which I did, and that was about four years ago now. It worked better than the original ever did, and I haven't had to touch it again.
I don't know if a CHIRP sounder is the same technology, but if you just use ordinary silicone rather than sikaflex, you should be able to get it off again fairly easily if it doesn't work.
A Boat is a hole in the water, surrounded by fibreglass, into which you throw money...
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