Click on the Federal Taxes tabs, Deductions and Credits right below.
Select to Choose What I Work On if you see that,
Otherwise, just scroll down all the way to the Other Deductions and Credits group near the bottom, and Update or Start the Other Deductible Expenses subtopic.
Say No to Generation Skipping Taxes,
Say Yes on next screen titled Less Common Expenses.
Enter a Description (such as Overpayment under REV Rule 79-311) and Amount