Wiring question

The relay that comes with it is to energize the switched circuits when the bike is on. They recommend hooking to tail light in some cases.
In other words no it would not replace the other relays like on the horn.
 

I would strongly recommend using your current relays, you don't want that much power going thru the switches. All your doing is "cleaning up" where the relays are getting their juice from.
 
I've bought several wiring devices from Eastern Beaver, for my motorcycles. He makes good stuff. I highly recommend his products
 
just ordered a power centre and a couple relays, thanks for the link