Well without having a repair manual to guide you it will involve you disconnecting anything attached to it, support those items if needed as sub frame is removed and then reinstall and reattach all that was unhooked. Will also need to have the alignment checked for proper adjustment. Sounds like a large undertaking unless you have patience, good tool asssortment and knowledge. I would not tackle unless can elevate car to allow for plenty of clearance and unless you have a manual that helps with unforseen warnings as to what to expect. I bet this is quite the job at either a frame shop, body shop or qualified repair shop.