I'm trying to make my own 747-400 variation and noticed I could open the Boeing747-400.cab file and extract it to get to the gauges and stuff. So I did the extraction, utilized GIMP, and now I'm stuck at the part where I make the new CAB file. I used the FS2004 SDK to make a new cab file. It worked mostly, except for the part where the instruments looked scrunched up and misaligned. I tried to install the SDK for FSX, but it refused to install because I don't have the original SDK installed because I don't have a disk where I bought it on Steam.
So now I have my textures all ready to go, but no way to put them into a CAB file that FSX can use correctly.