Hi, thanks for the reply.

wipers - The motors were both working fine when taken off, they have been stored correctly so I can't see both would fail? I will check for voltage though and get back with a reply.

handbrake - should of thought of that lol

monitor - I do have a spare control unit so I will try that, is it possible that incorrect bulbs have been fitted? Although what you say about earths seems sensible. Would earthing the rear light clusters directly to the chassis be the first step?