Because the mounting screws for the #1023 tilt up base can be accessed with the downrigger mounted, consider replacing those with some keyed ones (aka security fasteners). You get the locks on, but it doesn't stop someone from simply backing the four screws out with a hand held screw driver and walking off with the 1023 base and consequently the downrigger.

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RIP Tyler Greer. May Your seas be calm, and filled with "tig'ol'bings"!