Ever since SW has introduced the mirror components I have had 0 problems with it until now...   Picture if you will a top view of a rectangular box, I am trying to mirror the right wall of the box to the left side, simple right?  Well check this out

Step 1 select the right wall

Step 2 a preview of the wall being mirrored to the left side with RIGTH PLANE selected as my mirror plane (I don't typically need to reorient it, I am just in this step to show everyone a preview)

Step 3, What the heck went wrong? It shifted my whole wall by some odd ball number, approx 7/16" off

Test and Theories, here is what I have done

1. I have went back to make sure my assmblie and parts involved are all built on center planes

2. The default Reorient compoment option is "2 of 4" which basically flips the wall to the other side, the way I want.  If i select 3 or 4 which turns my wall upside down it brings the wall to the front like it suppose too but however it will shift the wall 90% off to the right (using pic 3 as a reference)

3.  If I chose option "1 of 4" my wall will be cenetered perfectly, but it is upside down which not a good solution for other reasons.

4.  If edit this feature and I pick other components in my assembly they mirror perfectly.