A radio wave cannot travel thru chicken wire, 1.5" circum i.d., as long as it's grounded.
Outside of that a GPS/glonass frequency noise generator or (jammer) is effective also. Or a aluminium foil covere, grounded to circuit or earth nearby.
Any other ways too.
The alarm on it is 48v, Shortt out the GPS module with a piece of wire with alligator clips, sharpen teeth, clip on 48v supply, jump start the GPS or controller and it will cook off.
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