Check to see that the wires are tight on your ignition switch. So many people tie accessories in and out directly on the switch that I found erratic starting to be the exact problem on an old car I have. Keep in mind that electrical problems on older cars are caused by wiring problems far more often than component failures.[/QUOTE
Are you reffering to a Dash mounted Ignition Switch?
Mine is a 75, so Column mounted ignition. I have pulled and proded the wires from the switch but have not discovered a loose wire yet. PO changed the ignition - probably trying to find the same problem. He failed to mention it though. I got a good deal so expected some things to be off.