All this talk of Block Heater's got me to rewire, this time with a new extension cord with a better rating and fixed 3 prong plug, from outside through the grill, to under the hood.
At Home Depot I found a $11 -9' Black Husky Medium Duty Tool Replacement cord that was rated at 15 amps, and 1875 Watts Part #110860 that has a quality, grounded, 3 prong Male and had bare wires on the other end, which made it easy to feed in the left side of the grill, through a rubber split square opening.
Then the cord went left, got zip strapped to rad frame support, and over to beside the air box, where the female connector was installed.
I moved the 3 prong cap off of the stock block heater cord to the front of the new extension.
Tested extension with a light bulb, then plugged into block heater.
Total time 1 hour and less than $20.\\
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