Ralf - it's an inboard headlight Shelby. I would not use the front wiring harness as an example for other cars. I'm left scratching my head as to why the high beams are wired the way they are. Four intrusions into the harness when two would have sufficed. The Ford home office was not consulted.
Here is the regulator side. Yes, I have properly fixed the very apparent modification. It's hot down south.
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Like Jeff says, you can't make out if the plugs were there or not. Only illustrating what I found on this mostly unmolested car.
Getting back to the when the change was made from round/oblong/square, it might be better to drill down on the stamp date of the radiator support. Different plants probably had different supply levels of this part. Without knowing their initial supply and how many cars were cranked out at any time you are solving for 'x' when the y' variable is also unknown.
Do we even know if only Cleveland made a radiator support (like mine?). If others did you now have another variable in the mix.
My back hurts so I'm on the couch reading through a bunch of posts. Just in case you wonder why is Bill going through old posts dating back months and months and months.
