Heidelberg SM 102 8 P yr 2000, Image location on plate?

Where does the image start on the plate when burning it in prepress? I have a customer who keeps getting the image wrong. When the plate is burnt and put on the press, the image runs off the sheet because they keep moving it too far back towards the tail edge. I told them it has to be closer to the lead edge / grippers. I did a quick measure with an old plate and a printed sheet. I came up with 37 mm for the plate from the gripper edge to the edge of the sheet, plus an additional 17 mm for the image to print on the sheet. Does anyone have the correct measurements?

 

For SM 102 its 52 mm at gripper edge.

 

Thank you