Complex sentence: Its Junkers L5 engine was mounted in the nose and neatly cowled, with its oil tank aft of a firewall and a retractable honeycomb radiator on the fuselage underside.
Split into simpler sentences: Its Junkers L5 engine was mounted in the nose and neatly cowled. Its oil tank was aft of a firewall and the retractable honeycomb radiator was on the fuselage underside.