Parts? Why do I always get screwed?

[KingKole02]

I order a so called "second horn" from JCwhitney from a recomendation of another PT owner that has done this. They own a series 2 dreamer.

I paid 20 something for it and it came with less parts then the $9 one at a local shop. I had a banana wire connector, ground line that was about 4 in. long and 2 wire connectors to go on the banana connection piece. I was told it would just plug in to the factory wiring. Yeah right, after I cut all that out, then maybe. The factory wiring harness on an 03 look like a plug outlet.

Where can I get a horn that will just add to the 03 factory wiring beside going to the dealer and being charged whatever they feel like charging for one?
Im not one to cut into wires I have dealt with before without knowing the side effects.