CHuck - those are the "side Inverted" mufflers. The "Pitts" is normally configured to "wrap around" the cylinder, engine inverted, such that the canister is cross-ways under the engine box, and the exhaust tubes point down near centerline of the fuse, and cant slightly rearward.

Pic attached is NOT a DL 50, but is a good example of a bottom view of a Wrap Around PItts-style muffler.