The M/W rotated the bolt circle to clear something. Found this out after making a pinion support with a stock Ford case for mock-up and then the customer said the plate did not go on when he put the race unit in the car.
The problem with what you are asking is that there are different ways to get measurment , either Datum or X-Y cord and your ability to transfer those to the material. Do you have a pinion shim that you can scribe from?
