You will not stop someone who is really keen, but if you can delay the time it takes to knock off a car it will solve most problems.
A block of wood Velcroed under the accelerator. A quick & easy second line of defence to a chain. No idiot in a hurry will think to look to remove such obstacle.
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Procrastination, mankind's greatest labour saving device!
50L custom fuel rack 6x20W 100/20mppt 4x26Ah gel 28L super insulated fridge TPMS 3 ARB compressors heatsink fan cooled 4L tank aftercooler Air/water OCD cleaning 4 stage car acoustic insulation.
On my diesel . Have a cut out switch on fuel . Plus no starter by open circuiting auto safety switch . Both done
through elect wiring . Very easy . Also have cameras outside on solar /roof . Plus most the time its up on hydro stabilisers . Good luck getting them down as they have seperate hidden switch also !!