Making a car difficult to steal

Of course they can power the starter. They are known as "jumper cables." Every good (pro) thief has a pair. How long did that take?

What is the circuit titled "security interlock" and how is it powered?" The thing is, if you can keep them from jumpering power to ignition, fuel pump, etc, it won't run. The only thing they can do is tow it or haul it, whether the starter cranks or not. What if it's a stick car? They can push start it So you need to get power OUT of the hood area.

My car, EG is EFI and uses an electric pump, so there's several options there. You hide the power to the fuel pump and the EFI. They could spend hours trying to chase that down.

But if they have time, and the isolation, they could back up there with a tow truck and be off

Here's what I'm planning.............some sort of pre paid cell based GSM / cellular device. Even if it's not an active ALARM, it will allow TRACKING. Any law enforcement can silently call the thing through the phone co. if necessary and have it tracked as long as it's not out of cell range and as long as it's before the battery in the car is cut, allowing the cell battery to go dead. With modern devices this might be a couple of days time, anyway. I realize, that "in the wilds of Montana," etc, there are places that don't have cell coverage.