You can get both world if you are willing to do the work.
The switch needs to be a 'CLOSED' connection when the trans is in neutral.
Check this with an Ohm meter ( your average DVM for $5.00 can do this ). If it is closed, the resistance reading will be zero or very close to zero.
Run two wires to the starter solenoid. Remove the wire from the key ( this should be the small wire ) and connect it to the key wire.
Look if you have two big wires and two small wires, one is the resistor bypass and you do not want that one. You can test by jumping ( with the car in neutral ) from a small wire to the battery. If the start engages, that is the wire from the key.
Anyway, connect the key wire to one of the wires from the neutral switch. Connect the other wire from the neutral switch to the starter solenoid.
NOW, if you want to over ride this switch for any reason, place a panel switch in the dash that is wired across the two wires you dragged up from the neutral switch.
If you need to start it in gear, flick the switch and rock and roll.
Hope this helps.
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