Help with horn wiring on fld120

Hey all. Got an issue that I need some help with. I have a 1999 Freightliner FLD120. It has an aftermarket steering wheel on it. Looks like a SCI but it does not have any marking on it. So I put a city horn on it and found that the horn wires were wired tied up and not used by a previous owner. I hooked it up and it just blows the horn constantly. I took the horn button off and there is 1 wire that comes up thru the column and plugs into the back of the steering wheel horn button. As soon as I put the horn part in contact with the steering wheel the horn starts blowing. I thought maybe that it is grounding out or something on the wheel but I don't see any issue. Obviously doesn't mean there is not, but did not see anything. I do know that in the manual it shows 2 wires coming up thru the column where I only have 1. It is a round what looks to be brass part with a inner cardboard part that is over the column. It then has a wire that goes to the side of the column and is attached to a terminal where a wire is screwed on. That wire comes from under the dash. And then off the brass part there is the wire that goes up thru the column to the horn button. So I didn't know if anyone out there is familiar with how this thing should be wired. Thanks for any help.

 

Ok nevermind. Just found out that it is missing one of the insulators on the horn mechanism so it is grounding itself out. Thanks