General Technical Questions and Answers last answered over 1 year ago.
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I put mine under the drivers seat and it's in the main earth lead from the battery to the body. I've put a low value fuse around the switch so that the clock keeps going and so that if you do put the key in and turn the ignition on it looks like it would work - but when you try and crank then it blows the fuse and won't start. I've only forgotten a couple of times!
And if you think that under the seat is a bit easy to access for tealeafs then I also have a hidden switch that breaks the main feed to the ignition. But I'm not going to tell you where that is - otherwise I'd have to shoot you!
I saw a bay with the switch mounted in the rear panel above the engine bay (externally)- the tube the key fits into potruded slightly. Thought this was a bit odd but there must be some reason for it?