Regarding your wiper, if it continues to operate after you switch it off the problem must be either the wiper stalk switch shorting out or the relay sticking shut,I would try the relay first. It is in the compartment at the back of the main fusebox in the engine bay;Part#.0025421419 I think.Before replacing it open it up , give the contacts a squirt with contact cleaner and see if that helps.
Cheers, Geo.