Right on RoadRunner,agree with your position, and hope this picture helps.
In my case the Jig was already supporting the cars weight at the front and back ends. Before I cut a single spot weld loose a wooden support system was built that picked up locations identical to where the springs would normally support the car, I used a central support in the axle location tied into the lower jig supports, this allowed me to move the car during work and further mimics the loading seen with weight on wheels. As already stated, take lots of dimensions (and pictures), even things you cant imagine needing since once its cut loose its to late when you find you need an additional measurement.
Only variation I have is I cut all panels off at once and found it much easier working in an open area than trying to work around existing panels that were going to be replaced. I must warn you, this is not for the faint of heart.
Take your time and cleco or clamp everything together and you'll be fine.