Frame Off: How can i get the body off?

[Volker_Germany]

With my 70 Panel we think about a frame-off...

But we have some problems.....

1: How easy is it to get the body back on the Frame?
2: the wooden panels in the back: are they over or under the body? How we can replace them? Anybody has a pic documentary about that?
3: Size....I have seen that some body parrts are under, some over the wood. The small and easy point is that the thickness of our wood what i can buy in Germany is in mm, but the us is inches...What if i use wood that is a little thicker or thinner? Will the old parts fit or do i need to import US Wood?