Are you reporting a liquidation distribution? I can't find a specific screen for it in the interview. The simplest way to get code L in the interview would be to call it a sale of personal items. When TurboTax asks "Do these sales include any other types of investment?" click Yes. Then when you get to the screen where you enter the details of the sale, one of the choices for "What type of investment did you sell?" will be "Personal items." This will give you the result that you want on Form 8949. The IRS will not see that you called it personal items. That's only on an internal TurboTax worksheet. The IRS only sees what's on Form 8949.
As an alternative, you can enter it as an ordinary sale of stock, then check the "nondeductible for another reason" box on the Capital Gain (Loss) Adjustments Worksheet in forms mode, as jtax suggested last year. Making an entry in forms mode does not void the accurate calculations guarantee as long as you do not use an actual override. Just checking a box or entering an amount is not an override. An override would be shown in red on the form. If it's not red it's not an override, and the accuracy guarantee is still in force.
