I have managed to understand how I am taxed for my dual status tax year, but have not grasped where to enter my income on 1040NR (I filed 4868 earlier).

I was in the US until September 2012. I have to send a 1040NR return with a 1040 statement. The 1040 statement I can complete easily and I have no US taxable income for the non-resident part of the year. So in theory it should be simple. But ultimately I have to transfer information from the 1040 to the 1040NR and the IRS have failed to give me any clear instruction on this.

The best I understand it, the deduction and exemption is handled on 1040 and taxable income - from box 43 on the 1040 - is then transferred to the 1040NR. But to which box? This is completely unclear. Do I put it in into "other" and write "taxable income from form 1040"?

Also, because of my unusual status I am am able to claim a tax treaty exemption despite having been resident (long story). Last year this was done by entering negative income into box 21 of the 1040 and adding a statement to explain. It seems like I do the same this year - but then how do I handle the tax treaty part of 1040NR? Considering that ultimately, my US tax should come to zero this whole thing has cost me far too much time and stress already. I'd be incredibly grateful for a clear answer.