I'd rig up a way to keep the hatch closed from inside and would keep my .45 close by. I find that a large caliber handgun is universal for go away. If a gun isn't a possibility I'd go for a bat or even stealthier a shovel, either one will do plenty of damage at close range. The mace or pepper spray seems like a bad idea for an enclosed environment.
2013 Toyota Land Cruiser
2008 Range Rover HSE - RIP
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