Well, that may work for the switch, but what about power? Either way its up to you. PIAA doesn't recommend running lights that way, but it could be done. You'd lose some power as the relay would be trying to convert to four lights instead of two - which it could do but shouldn't have to... isn't the kit cheaper anyway then buying two lamps? Either way... I'd advise against it. I have mine wires up seperately. Today I spent all day re-installing my old PIAA's, installing my new PIAA's as well, looks like that's what I'll be up to tomorrow as well. Here's wht I had planned for the day...
-move two switches (the ones that control the 80 XT's on the roof) from under the dash to the ceiling.
Move wirign so that rather then going all around the car we now take the shortest route - down by the drivers side door.
-Add one switch on the ceiling for the new set of lights on the roof.
-Hook up the new sets of lights (three total)
-Change the PIAA 520 fog light switch to use another switch - one of the two switches that came with the PIAA 80 Racing... I'll explain that later.
-move switches under the dash that WERENT moved up to the roof to a different location under the dash to allow installation of new switches.
-remove old CB, install new CB
-remove all unnecessary wiring from system.
I'm still working on it... of course it doesn't help that while drilling a hole in the frame to use as a ground I broke a drill bit and had to spend about an hour looking around in the engine compartment for it... so far I've been screwing around and haven't even gotten around to getting the new ones working yet - mainly been fixing the problems that I created teh first time I installed the lights, which was in an extreme hurry to have them hooked up by Truckhaven 2000 in about 50 degree weather....
Here's some VALUABLE tips I've learned (you know what they say... better to learn from someone elses experiences then make the mistake yourself...)
1) When it says remove your negative battery cable, oh brother you had better remove your positive battery cable as well just to be on the safe side!
2) Pay attention while saudering... the smell of burnt plastic (surrounding the wires), allbeit better then burning rubber or burning hair, is still not a good odor.
3) Label ALL your wires, and both ends of your wires, if your planning on cutting a bunch of them and moving the wires to new locations where they could easily be confused with other wires.
4) Take notes of all wiring that you do, and don't hide the wiring behind panels until your done with the install, I can't stress that enough

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5) Check before drilling holes in your roof... If you are lucky enough to select an area of the roof that is part of the frame, feed that wire down all you want, it will do you no good, you'll never find it.
6) Check wire lengths before cutting and splicing
7) Check that your switches are where you want them BEFORE drilling them in to wherever you are putting them.
8) If the switch don't call for a ground, don't try to hook one up! (said four fuses later...)
Seriously though, the PIAA's are cake to install, when however you try to just about re-wire your hole vehicle and keep messing things up, it makes it a bit more "interesting"

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By the way, if you go with 2 sets of 80's on the roof, one set of 520's on the front, you'll have the same setup as me and Ray (before I added the other 6 lights)