Thanks all. So my "physical interpretation" would be to have a block with a flat plane that would rest on -A-. In most GD&T examples, you would then have a 90° plane that you would slide against the secondary datum. In this case, that second surface would be at 100° instead, you'd slide it...
I'm trying to agree on a datum system between my engineers and a supplier...
The part has two primary functional planes, unfortunately not perpendicular. Normally one plane would be primary, slide against the second.
What is the proper way to establish a coordinate system from these 2 planes...