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Mentor
Mentor

My usual workflow is something like this:

  1. Make sure there is a dimension style in the drawing document or style library that meets the new requirement.
  2. Select all the dimensions I want to change (Try Shift-RMB and the Select All Inventor Dimensions)
  3. Go to the annotation tab and use the style pull-down to select the new style.
  4. Inventor will apply it to all the selected dims.

You might try the Copy Properties command in the RMB menu, if you want to make a few one-off changes to specific dims.