I'm still finishing (and cleaning) up from the installation, but eventually I'll have it probably half full of random hardwood, if it ever stops raining.
Shed is about 7'x6'x7' with about a foot roof overhang. I'm debating putting sides on it or just adding a few more horizontal boards to keep the stacks in.
Boiler is a Central Boiler Classic Edge 350 in stainless steel which is now doing duties feeding the hot water heater and forced air furnace.