parts:
1 relay
16-14 gauge Wire (lower is thicker)
4 female spade Wire Connectors
3 ring wife connectors
3-5 um forgot what they are called but they splice 2 wires together
1 set of harnests
1 inline fuse
tools:
wire snips
connector crimps
wrench
optional parts:
shrink wrap to make things look nice
ok set one is getting everything
you want to install a switch(button) inside your car one side to positive power and the other to pin 86 on your relay
Then connect pin 85 to ground (also negative)
ok now you want to take the postive lead from the harnest hook it in to the 30 pin on your relay.
ok almost done. now you want to put a conector on the end of your inline fuse and connect it to pin 87. (i'll explane about the fuse at the end) then connect a longer wire and run that directly to your battery postive terminal.
last part is selecting your fuse use what they reconmend.
here the only picture i have from mine
top wire being pin 30 (to the horn)
bottom being pin 87 my fuse conneced in from the battery
right being pin 86 the wire from the switch connected to positive.
left being 85 the line going to ground.
also there are 2 diffrent types of relays you might find single pole and doube pole. it come with an extra pin 87a. for this do not use this type because pin 87a always has power going to it when the lights are off, and you would be leaving a large open power sourse sitting there.
ummmm this is a copy and paste from my harnest upgrade post, it's the same process, just now your installing your own switch and wires for it, to activate a relay you need to put the switch on the positve side (pin 86), you can use ground (pin 85) but our cars are negative ground and chances are your relay is made the same way too if something was to go wrong internaly it would shoot the current to ground. connect both horns to the same relay and switch, and just connect to negitve wire to ground (rember ground is negative in most cars). also if your worried about the switch having too much current dont, the switch only activates the relay that can normaly handel around 30 amps (or 360 watts)