Is there a way to manually change the South Carolina Retirement Income Deduction Amount? My wife, on disability, with no SC taxable income is not entitled to it.

My wife and I file a joint return.  Federally, most of her disability retirement income is taxable.  Within South Carolina, her income is not taxable.  Since she has no taxable income in SC, she is not entitled to the $3000 retirement income deduction but I have found no way to remove this deduction within the Turbo Tax on line software.