Move position of all motion keyframes at once

So I've got two scenes - the original where image on the left and text on the right; and the duplicate where the layout is horizontally flipped, image right and text should be on the left. 

I've pasted in the text from the original version and just need to move it to the left so its not crashing into the image.

The text is animated from out of the bottom of the screen, pauses in the middle to be read, then moves out the top at the same speed as the image.

I just want to move the position of the text to the left, have this effect all the position keyframes.

I only seem to be effecting one KF. This is driving me nuts. You'd think it would be simple.

Any help appreciated, thanks.