The switch requires adjusting,put the gearshift in park and loose the screws so you can rotate the switch,keep turning the ignition till the starter engages then lock up the screws and retest. Then put the gearshift in neutral and see if it starts there as wel;l as in park. Also test the backup lamps they run off the switch as well. I hope this helps. Garry
Switch mounting is very sensitive. Try moving thru all the gears and try to start the car. If it trys to start in Rev or Drive, adjust the switch till this positon is Neutral. I had to do this with my 69. I am assuming you have a floor shifter. If not a column shifter should work smililar. Also try jumping out the switch to make sure you do not have a defective switch.