I submitted my '16, '17 and '18 returns via TurboTax but they were rejected for IND-031-03, incorrect AGI. I left them until right now to fix. Part of the TurboTax filing instructions, included with my downloaded return, instruct me to mail an 8453 with an 8949 to the IRS, but nothing else. The instructions say the IRS already has a copy of my return. Is this correct? Or do I still need to mail in a 1040 with an attached W2 as well as the additional 8949?