Importing from QuickBooks. Which Tax Line do I assign Income from SAFE Notes?

I believe you are asking about recognizing income on your tax return from the issuance of Simple agreement for funding equity (SAFE) notes. If so, the money you received would not be income, it would initially be a note payable and when and if converted to stock an ownership contribution to the company. As such, it would appear on your balance sheet as a liability (note payable) initially, and if converted to stock later on, on your balance sheet as a component of equity (common or preferred stock.) Since it is a balance sheet account, it would not appear on your income statement and would not be taxable on your tax return. So, it would be a liability initially.