If the car wont start try jumping it at the soleniod. If it starts I would guess that the clutch switch is the thing your missing (Neutral safety switch) I know you dont have one, but how can the car run if you dont. The key is triggered by a white/red wire. Fromt there it runs through 10 sensors, if any of them fail the motor wont crank. Just my 2 cents. The wire that runs all this shit is red with a blue stripe.