Location of where reaction forces and free body forces are referenced from for cynlindrical hinge

Hi everyone,

I was wondering where the exact points the reaction forces and free body forces are measured from. My point of interest is in the middle (such as cutting the assembly in half and in the center of the circular cross section of the rod) of the small rods and finding the reaction or free body force there, but not sure how to do it (I've attached some screenshots for clarity). Any suggestions would be great. Thanks.

SolidworksSimulation