kill switch

Hi, new to this (in fact any) forum so please excuse me if I am going about this wrong, my dad just brought a T4, 2.4lt, W reg (2000), someone has hacked about at the electrics (honestly, there was wires jammed in the front of the fuse panel), and added a kill switch, enter my father, who on...

i want tobe able to cheaply/ easily immobilise my van (ex aa) when camping abroad. i have a couple of those battery cut out key kill things in the back to isolate the leisure batt and charge circuit. would it be sensible to wire another one in under the bonnet between the batt terminal and the...