Documentation/Tools/Game Archive Extractor
You may use the provided extractor to unpack the game archive to develop game mods. To repack the archive again use any standard ZIP utility like 7-Zip after you've finished your mod.
scs_extractor archive.scs [output_path]
You may also drag and drop the .scs file onto the SCS Extractor to extract the files. Dragging the base.scs file onto the SCS Extractor will extract all the containing files into the current location of SCS Extractor. To keep extracted content out of the game's original directory, you should create a separate folder where you place a copy of the SCS Extractor. Then just drag the game file onto the extractor. The console window will close once all files have been extracted.
Download the extractor here.