I discovered a different way to accomplish my goal.

Assuming a document that has lines of text that start with a business name, followed by the address and ending with a phone number, and I we want to put the dots tab before the phone number.

Determine the inch measurement of the leftmost digit of the phone number when it is up against the right margin. We'll use 6.69".
Highlight the entire document. Control A
On the Home tab, Paragraph box, click the tiny icon in the lower right corner of the Paragraph box. This will open the Paragraph window.
In the lower-left corner of the Paragraph window, click the Tab button.
Enter 6.96 into the Tab stop position box.
Click Right for Alignment.
Select 2 for Leader.
Click Set.
Click OK