Clicking sound after spiral cable replacement

Had the spiral cable TSB done.
Now, there is a random clicking sound coming from the area around/in front of the steering wheel or dash - most pronounced at 60+ mph.
Sometimes, turning the wheel to either side - like going into a curve - stops it.
Took the truck back to dealership. "Nothing in there which would cause a ticking or clicking noise".
They poked around in the dash area and noticed "non-original wiring" from extra lights we've installed. "Maybe the problem is from add-on wiring".
They want $360 to investigate.
Any thoughts??

 

Yep.

They don't want to mess with your truck or admit they may have caused an issue. Love to use modifications to deny service.