Grandsons '93 Grand Marquis Power Door Lock Solenoid on front passenger door pulled through the door sheet metal (she fractured around the solenoid retainer). Is there a mod for repair or will I need to place a large washer behind the suppport nut to keep it from pulling through the door sheet metal. Also, how does that retainer come off of the solenoid, is it a very small nut or does the large, hat like piec just twist off?