How to import 2D position data into After Effects
Found the answer here.
Copying any positional keyframes out of After Effects generates a text file like this:

Adobe After Effects 8.0 Keyframe Data

    Units Per Second    25
    Source Width    100
    Source Height   100
    Source Pixel Aspect Ratio   1
    Comp Pixel Aspect Ratio 1

Transform   Scale
    Frame   X percent   Y percent   Z percent   
        100 100 100 

Transform   Position
    Frame   X pixels    Y pixels    Z pixels    
    0   960 540 0   
    1   980 540 0   
    2   980 520 0   
    3   1000    520 0   
    4   1000    518 0   
    5   630 498 0   


End of Keyframe Data


To manipulate it, just modify the text, copy the text, and paste it back into AE.  Works like a charm