Here's some under hood pic of my 69 B-Cuda Slickback. The wiring as far as I know has never been messed with, and I've had this car 25-30 years.
The worst thing with these turn signal lights is replacing the bulbs, and getting them to work again after taking them apart. They are finicky.
Harrison, you can probably pull the wires thru all the holes with a long stiff wire, or a coat hanger.
Dave
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