Don,
If you think the horn is bad, take a 12v wire from a good known sorce(batt) and touch the horn lead. if it honks =horn works and it is in the wireing
if No honky = bad horn.
If it is in the wiring, just use a toggle switch( (or momentery switch) in the interior from the horn and hook it directly to the horn and a 12v refrence. so the horn will honk when the switch is used.
That will get you past the inspection for the time being, then later you can trace the horn wires at your lesure.
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98 3800SC GTP motor,3.4 pulley, Getrag 5sp.
custom hood, trunk, side scoops, IRM front spoiler, 17" excel's , dk.Shadow Grey