Car won't start - bad ignition switch?

Frozen,

You are correct on all - remove starter clip after it cranks and fires, leave IGN clip on. When you remove it, the engine will stop. The 3 smaller blue wires sounds like the upstream side of the ballast (normally powered thru the key switch). Your clip is doing what the key switch normally does. On the upstream side, the 12 V feeds in (IGN1) and continues to Vreg and alternator (later cars). I don't know what the 3rd blu wire is. Check your wiring diagram. Maybe a choke heater or such.

Others are correct that I was telling you how to solve more that just your initial problem. If your key switch is erratic, besides not cranking you also may not get ignition power. A few jumper wires can get you home. If your key switch is in the dash, it is easy to remove and cheap. If in the steering column (changed around your year), not easy, but there is a great sticky post w/ photos.