The option you have selected under 'List Result Force' is "Reaction Force" which is a particular measurement that queries from model items (faces/edges/vertices) that you have applied fixtures on. So, in your case, you would want to select the bottom faces of the blue body instead of the top. What I am expecting you will find is that the force as the fixture is equal and opposite of the applied force (1000 lbs) regardless of the length of the clamp arm you make because you are still applying 1000 lbs of force to each system.
If you are looking to see what forces are coming through the selected face you would need to switch over to "Free body force". Even in this case though, since the blue model is still resisting the same applied force the Free body force value would be unchanged between these systems (within error).
Thanks Ryan for your help.