Create Action That Makes Guides by Percent

I'm attempting to make a Photoshop Action that creates a series of guides by percentage. I start  recording and create a horizontal guide at, say, 30%. But when I go back and look at the action it always converts to real pixels. That's a problem because I'm creating square images that need guides in the same place but are sometimes different sizes. Is there any way to get around this?

Thanks!

Darrell Leland