Titles at top of iMovie frames

[GD2]

I'm looking to add titles to an iMovie at either top-left, top-middle, or
top-right of a few frames; basically an overlay onto the movie. Something
like iMovie's stock titling effects, but I need them at the top of the
frame. I can't seem to find any plug-ins that do this, or at least their
descriptions aren't making sense to me. Will someone point me in the right
direction?

Thanks -
Gene