99 alero ignition and 12v supply wires

I' m using the wires that come through the firewall to hook up my avital 4113. I have found two heavy gage pink wires that are ignition, two heavy orange for accessory and 4 heavy red wires for 12v. My question is do I just need to connect to one of the pinks and oranges or do both need to be tied in. Also will I be able to  use any 2 of the heavy gage reds for my 12v supply? Thanks

I actually took out the radio last night and hooked up a second ignition and the second accessory.  I only get to work on this car a few hours a night and then it has to be ready to drive so I'm doing a little at a time. It's so much easier to get at the wires coming out of the firewall, many others on this forum do it that way. I will just do a little more checking tonight but I'm positive that I can catch the accessory, ignition and starter wire down by the firewall.  I don't install remote starts for a living but I'm guessing an alero has to be one of the bigger pain in the asses to work on! :)  It was a f&$#cking pain just to solder those two wires up last night, I didn't pull out the iginition switch I just stuck my fat hands in there and did it.! I will let you know how it turns out. Thanks for the help!