Need a little help tooting my horn.

Here is the situation. I have a 92 Mercury Grand marquis, and I am changing, well more like ADDING a second horn to it. I want to keep the original horn it came with, but I also want to add a secondary horn, specifically the OOGA horn from Harbor freight. I've tried looking online on how to get it installed, but everyone has been using this as a replacement for their primary horn which is not what I am looking for. I have plenty of wire, a push button to install to use as the horn button, an in line 30A fuse (that's what they recommended) and have a relay, but I just can't wrap my head around the wiring for some reason and decided to come here for a little help. Diagrams would be greatly appreciated.


Also I should note that this will only be one part of my system I plan on adding yet another set of horns at a later date. Since this car was referred to by the previous owner as "the boat" and well, it basically is..... I was going to also add (eventually) an air horn as well which I know will be really interesting with a compressor.

Take your pick:

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