RMH in a shed as a backup to solar dehydrating. Plans?

I'm about to re-do one of my sheds and I'd like to make the front into a solar dehydrator mainly for drying apples. Some autumn days are perfect for this here in Vermont, other days... not so much. So I'd like to incorporate a RMH in the floor or along the back wall, bench style. I think the pebble style will be faster and cheaper to do.

What I really want is to purchase plans! Who can hook me up?