Anyone have any experience of modifiying crash bubbles of non-stock aircraft for CFS2, and if so could they give me some advice on how to do it?

Mdledit allows adjustment of the stock and ai flyable aircraft, but nothing else
I notice that DpEdit will allow you to change 'scale' to 0.5 but I wonder if this is the model that is being changed or the damage boxes - or are both necessarily linked?
Don't know how this works, so any input would be greatly appreciated
All the best
Pads