Duplicator 7 Z Axis Angle Test

This may be a fix for some people... I was getting slanted parts from my machine. I noticed on a test strip i use as a demo part. You can see in the image of three of them (bottom one was purposely stretched in Z to exaggerate the issue) The top one is after i have shimmed and packed the z axis rail to make it 90 deg to the build platform in X and Y. The lower two are printed before the fix. You can see they are 'leaning' when they should be square. I have designed a X to print on the build