just bought 8n ford

   / just bought 8n ford #12  
old coil new ballast resistor

Do you have a multi-meter to measure the resistance of the old coil, and new ballast resistor? In some cases, you need both the OEM ballast resistor, and an additional resistor to keep the current low enough to prevent cooking the old 6V coil.
 
   / just bought 8n ford #13  
yep. oe ballast resistor always needed.

from there.. if it is a 6v coil.. you also need an 8ne10306 resistor.. or need a newer 2.5 ohm '12v' coil.. etc..
 

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