Hi Harry
I have taken my caravans windows out but never taken the front panel off!
The windows on mine slide into a rail and are retained in position by black plastic sliders with a small screw. Undo the screw, take out the black retainer, then slide out the window (definitely recommend you have a second pair of hands to help) and so on until all the windows are out.
The Haynes manual is not bad on panel replacement but is lacking in detail. It seems that you take off all the rails, mine has one across the top and the awning rails on each side. The roof is gently lifted up away from the front and the same with the sides. Where any other retaining screws are I have no idea.
Hopefully someone on here will know, but it reads as if the panel should then just lift away apart from all the sticky sealant.
If I were you I would want to confirm what needs to be stripped out of the 'van on the inside as well.
There are some excellent websites by enthusiasts who renovate 'vans - I am sure "googling" to find those would be worthwhile.
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