Drop zones from Motion Templates

Hi,

I've created a template in Motion, and imported it into Final Cut Pro. The template has video drop zones in it. If I drag video into it, it works fine. However I was wondering if there's a way that I can instead point the drop zone to another layer in the sequence? This would mean that if I shift the template forwards or backwards in time, then the video would change to an earlier or later part of the video.

Hope that makes sense.

If anyone knows of a way to do this, I'd be very grateful.

Thanks.