On a 66 Ford F 100 does the voltage regulator mount to the fender well or radiator support? I am trying to reassemble a project I did not disassemble. LOL Any under hood pictures of mid sixties Ford pickups showing wire routing would be greatly appreciated.
Should be mounted close to the starter solenoid on the passenger side inner fender. Look for three small holes for the screws... The other choice would be the radiator bulkhead on the drivers side, Ford liked that spot too. I've never seen one on a firewall.
My 61 f100 has the regulator on the right inner fender, and starter solenoid on the firewall next to the battery. Your year may be different?