You could just remove the horn output from the RKE module. the module has outputs when triggered and each output leads to differing locations (locks, horn, lights, etc)
I would think you could just remove the wiring from the box that would normally lead to the horn.
Hmmm... Im gonna have to do some thinking on this one. I dont want just my fogs to come on. I am gonna get some other exterior lighting for my car that I want to come on with it also.:shrug: We'll see.