Traveling FF/GPS

I'll be traveling south to East Cape Baja for a week of kayak fishing this fall. I'm trying to convince myself NOT to bring my fishfinder but I just can't imagine giving up this opportunity. Does anyone have any advice or experience with traveling and reinstalling your fishfinder onto a rental kayak? As of now, I have the transducer mounted in the hull of my yak with marine foam and glue. I imagine their could be less invasive methods of mounting on a rental & I have also had problems  with the transducer  accumulating debris and dying on me. Any shared wisdom here would be much appreciated!

Duct seal putty.

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