Yes Jon, having the tools and equipment is the main part of it and a good workshop of course.
Thankyou Dave but the above sentence is the answer!

I gave the underside a lick of green prior to overturning as it just makes sense and the cammo part that is behind the wheel station. In fact the complete double bogie is done in the light stone according to the book.
As I was about to fit the diff I noticed that the spacer plate was missing and I never had a spare so I borrowed one and reproduced one. I guess I should have done two but that's life.