car won't start until I release the key from the cranking position.

The absolute best and easiest place to start is to see if you have 12 volts at the coil while cranking.
Bet ya don't, and bet the ballast resistor is why.
For no more than they cost, just get a new one and replace it if you are not sure about how to check for voltage, and where.

More than not, the ballast is the problem and not the ignition switch when these cars do what you are describing.