Alright, for anyone who is interested here is what I came up with:
These are various options for interrupting the starter. The power sources can be replaced with existing power sources, and the switches can be mixed with existing switches, put on a separate panel or skipped all together. Mix and match for unlimited options.
Here is a developed version, with 5 switches, 3 must be on, 2 off and if you set them wrong and hit the key a fuse will blow disabling the system.
Of course this has the same problem as any alarm or such system, which is that if the starter wires can be located and tied together, everything is moot.
The way it's designed I was playing with getting the swtiches to light, however they light when the first switch is on and the key is turned. In retrospect, it would be better to light them with key-on instead of key-start + switch 1, but I'm too tired to rework the diagram as it changes where all the power comes from.
You can of course substitute non-lighted switches, push buttons, or dual position to make things more complex as well.
Follow blindly at your own risk!