I scored the wood around the area I wanted to remove from the wall and then scored further smaller areas to lift the board in smaller pieces. Once I'd dug a piece out of the wall (the damp parts lift more easily) I used a Wallpaper Scraper and having slid the 'Blade' under the plywood I tried to use the blades natural spring as you bend/lift the board as much as possible. (Being careful not to dig too much at the Polystyrene)
The area behind the front cupboard once I cleared the 'damp' panel and some of the good panel away. Although seemingly dry to touch further down the board the damp meter was still recording a yellow warning (i.e. may need attention) So I cut all this out.
The Batton running along the roof is shown below and when first uncovered was Black! - As it's drying it is starting to turn back to its natural brown colour however is still quite discoloured.
I decided to cut all the wallboard out completely along the wall where I'd had a damp reading in order to give me a fighting chance of drying the whole thing out in one go. So I moved onto the inside of the wardrobe! I've also loosened the wall of the Wardrobe so that I can if possible fit one whole piece by sliding it through into the cupboard area.
Having spent 24 hours pondering! - I then moved onto the Bathroom and started to strip back the Wallpaper (which did literally come off in my hands!).....
I removed the Bathroom Unit which was just held in place by 8 screws and unclipping the water pipes for the taps...and making notes of the wires and how they where wired.
I then stripped the damp out of the wallboard in the bathroom the same way as I did with the 'living area'
Again the Batton was Black and the smell of Damp Rot was particularly strong in the 'right hand' corner of the bathroom if stood at the door.
This pic's a bit blurred but heres the Caravan as it now looks!
So the drying out begins!.... I'm having to switch the fan heater on when I can as my Extension Lead is struggling! So I think the drying out could take a while - but I'm in no rush!.... I've now taken the decision to chisel out small areas if polystyrene under the timber baton so that I can hopefully measure how well the baton is drying out as I can only see the one edge as things stand at the moment and even where seemingly dry the damp meter is still going off the scale once the meters pins have penetrated the surface of the wood.