I had a low rev rattle which I was convinced was coming from the direction of: a-pillar/dash/passenger door/sliding door. Every journey was getting stressful between my better half and myself. It was making my driving experience a bloody pain. I checked the wiper blanking plugs, found that the panel between the engine and battery was loose, sorted those, messed with passenger seat, no joy but thanks for all those tips. I knew that the actual map light module was loose but holding it while driving did not make a difference. Whilst driving to VW to get my leaking sliding windows replaced I pushed hard on the map light assembly and pressed down on the "floor" of the storage area, it felt unstable, "Eureka", mentioned it to technician who was sympathetic and said he'd check it out.
The window job, which I was worried about, was sorted without any obvious paintwork/damage issues or problems. The rattle which might have been caused by the conversion was blissfully gone.
Thanks, VW Cleckheaton, we got off to a shaky start but I'm chuffed now!