Car blinker relay

Hello,

I used to have a bunch of neon lights, cold cathodes, etc. in my car, and, well, I actually have a car I don't want to put a bunch of holes in, so, I've decided to put all those lights in the party room in my house, at least put 'em to use.

I am using a computer 350 watt power supply for the 12 volts.  What I want to do is wire a set of my lights up so half of then blink on and then the other half blinks on (as the first half blinks off) etc.  Sort of like blue, green, blue, green, etc.

I know how to use an 8616 relay to turn a +12v current into a 0v current- I currently use it in my sound-activated setup where one set turns on with the bass, and the other set turns off.

So really, all I need is to find a way to alternate 12v current and no current every second or so.  Conveniently, cars already do this, so I stopped at autozone and bought the cheapest blinker relay I could find.  I got the "Tridon Stant" 550 blinker (thermal, I don't know what that means).  The pins are arranged like | _ | and labelled L, P, and X respectively.  Although there weren't any number specifications, I figured they were 85, 87, and 86 respectively.So, I hooked up the 85 and 86 up to the power supply and then the 87 up to the positive end of a 12v indicator, and hooked the - end of the LED to the power supply's - wire.  When I turn on the power supply, I hear the relay click, but then the power supply turns off and won't turn on for a few seconds (the way it usually does when I short two wires).  Swapping around the 86  and the 85 has the same effect, any other combination of pins has no effect.

What am I doing wrong?

Oh, I suppose I should have mentioned.

I've looked at the simple 555 timer circuit that everybody in EE gives you.  I guess I could do that, but I am horrible with soldering IC stuff and I do not have the necessary equipment.  I'd prefer a more idiot-friendly solution, if possible, thanks.