For my RSU's the Tax Payment Method is Sell-to-cover. There is a small amount of money left over that doesn't go to taxes but I can't find where to enter in this amount.

"TurboTax allows me to enter the number of shares sold during the Sell-to-cover event but assumes ALL of the proceeds went to taxes but in each Sell-to-cover event there was a small dollar amount left over that was not sent off to pay taxes but deposited into my account."

I'm guessing you're using the "guided" RSU interview here and telling TurboTax the shares were sold for taxes.  TurboTax "assumes" nothing and, frankly, telling TurboTax that "these shares were sold for taxes" has absolutely no effect on your income tax return other than recording the resulting gain or loss.  The taxes have already been reported on your W-2 and that's the only place that the get reported.

The fact that you had a small dollar amount left over from the sale, over and above what the broker passed back to your employer to cover the tax withholding, is completely irrelevant.  The gain or loss on the sale is the only thing that's important.