Before I made any changes, I placed my digital protractor on the bed and zeroed it, then put it on the side of a round rod held in my drill chuck. At any rotation of the chuck, it claimed there was 0.5 degrees off of the correct 90 degree angle when measured parallel to the long axis of the bed. This was only to give me a rough idea of the "out of tram left to right" measurement.. I then unscrewed my dial indicator stand from the magnetic base and gripped the stand in the chuck. I mounted the dial indicator 6.75" out from the chuck, and took a reading at full left sweep and full right sweep. The dial indicator said that there was a total difference of 0.120" from extreme right to extreme left (which was over a total distance of 13.5"). I loosened off the locknut which held the head vertical and proceeded to tap the head untill the dial indicator moved .060" at one end, which should have put the table exactly at right angles to the spindle. After much tapping and friggery ((The head doesn't rotate easily) I managed to get the same dial indicator reading at full right and full left sweep. I then locked the nut back up, and rechecked with the dial indicator. All seemed to be well. Then to confirm that I hadn't totally messed up, I checked again with my digital protractor and got a reading of exactly 90 degrees difference between the spindle and the bed of the mill, measured parallel to the long axis of the bed. I will add here that the locknut and pivot on the head will ONLY allow the head to pivot left to right, not back to front, so I wasn't worried about tram front to rear of the mill. Once everything was finished, I made a quick CAD sketch of a triangle with a base of 13.5" and a rise of 0.120"----The resultant angle was very close to 0.5 degrees, so I am relatively certain that I have corrected things.----Brian