Step 1: Select the Hole Callout that you need the round off changed. Notice what style this callout is using.
Step 2: This callout is using the default style, ANSI (inch). The style is what drives the round off for the Callout.
Step 3: To edit the style:
a. Click on Styles
b. Dimensions should be highlighted by default
e. Notice the Round-off value. Edit this value.
f. Click OK. You can click Apply to apply this change to all dimensions/callouts that are using that style.
Step 2: Give this style a name which you recognize. I called this Ansi_roundoff_6 for example.
Step 3: Now I can click on the Units tab and pick the round-off to be 6 places.
Step 4: Click Ok. You now see that style created and in the list. Click Close.
To change the style on an existing callout, select the callout with your select tool. Then select the new Ansi_roundoff_5 style from the drop down list. The callout will update with the proper round-off.