If you get the harness really wet (like I did) a shop vac is handy to help remove the water, just stick the connectors in the vac hose end and they will get pretty dry - then use a water displacing oil like wd-40 (I use something called crc 2-26) to get anything missed, then just let air dry a day or two with the battery out of the loop. Compressed air is ok to help dry, just be careful not to 'push' any water into the PDP switch/connector if you have an auto, I just disconnected everything and made sure it was dry. This thing was a caked turd of oil leaks from a bad valve cover gasket for years so it needed it bad!