If you're doing this in TurboTax Online and you aren't 100% sure about the numbers, DO NOT pay or print your tax return or you'll be locked out from making any further changes to this form. The only way to input these numbers is when the Online version throws you the errors during the "Review" step, so if you put in the wrong numbers and realize later, you need to hit "Clear & Start Over" and completely re-enter everything in order to throw the error again so you can input the correct numbers. Found this out the hard way and spent 4 hours on the phone with support to find out that they have NO ability to disable this.
