It would probably be cheaper/easier to just sell your current auto trans civic and buy one with a manual trans already in it from the factory. You'll have to not only replace the trans but have to buy shift cables/linkage, a clutch pedal and master and slave cylinders, clutch hose/line, cut and modify the interior to allow for the pedal, you'll most likely have to change the computer and almost definitely the engine wire harness. Unless there is something particularly special about your current civic, I would not recommend spending any time or money on such a huge headache. (Just my opinion)