Turn signals not working, blowing fuse

Disconnect NSS/reverse lamp engine bay connector: reading is “1 .”
You mean 1 Ohm?

If so, then one of the wires or conenctors is touching ground.
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With the flasher unit removed, connector CE14 is a break in the circuit.
That leaves everything highlighted.
How about the wire in the engine compartment between the bulkhead connector and connector CE40 ?

It could be cross wire short, but there aren't that many wires that connect direct to ground.

I don't know what the wire harness looks like on your car.
The next suggestion might narrow it down, but it may not save you from taking down the harness and unwrapping a section or more.

Since you're not using the radio connector. Take the terminals out of CE 13 and cut there. That will isolate C1 and X12 from B1 and D1. Then see which two are still in touch with ground. Later you can install a new terminal to reconnect, or make a splice. You may have to add a bit of wire so the wires aren't tugging on the repaired junction. I've found some of the underdash wiring doesn't have much allowance for strain relief and the last thing you need is an electrical wire under tension.