My take on all of this is that you should isolate the radiator. Adding a ground circuit, and/or zinc anodes would ensure problems should there be a ground fault anywhere else on the chassis. Impressed current will quickly degrade the radiator.
Isolate it and change the coolant annually will do. I have yet to see a modern car without an isolated radiator.
Isolate it and change the coolant annually will do. I have yet to see a modern car without an isolated radiator.