Mock-up as it is at the moment:
The start of the paper roof shows where the 'B' pillar needs to be moved to:
Door hinge detail:

Haven't seen this type before, but it gives a much more realistic opening arc to the door. However, it means that I need to ensure that the mountings for the rear door hinges are very strong!
What the new body needs to look like:

The tailgate splits between the two handles - sorting the hinging could be fun.....
Anyone have any tips as how best to build the new roof etc?
Thanks