Surface/Grid and viewports – Autodesk Community

Ok, so I have a drawing that was based on an existing cad file from another engineer. after setting up our plans (viewports etc) on all our various sheets, we then received a final survey from another firm. It appears that the initial file was based on grid coordinates and the new survey was brought in as surface. We want to adjust our existing drawings to meet the proper survey at surface. 

Is there a way to change this such that we don’t have to revise all of our viewports etc? I know I can just scale our existing files to the defined scale factor from our surveyor, but that would mess with all the viewports.