[John Elphinstone]

Found it – the posts are correct here when they suggest using the Position X/Y cross hairs to adjust the starting position of the text crawl, however what toke me so long to work out how to do it is that I had already move that layer away from the center of frame and reduced the frame’s size – so when I tried to find the red X/Y cross hair it was outside my canvas window and so nowhere to be seen.
If you’re having trouble finding the cross hair – make sure the layer you’re working on is front and center.