757 night and day textures

Hi,i started a topic at captain sim and it seems that nobody is there. i need a little help by replacing the Captain Sim 757 cabin day textures for the night textures. its because i remembered that in real life the cabin lights remain alight while in the sim, the textures change within daylight, also in the cockpit... so im trying to locate the textures with dxtbmp, but id like to ask for a little guidance too, since i don't work much with textures...Also, im trying to change the lighting in the cockpiont and cabin, the lights are generally yellow not white in real life. now here i have the dxtbmp and GIMP for doing this but can somebody give me a hand on what to do? thanks a million.