Don.
I guess it would make it easier not to combine the bedplate structure and the diesel airshaft, they really don`t relate to each other as the diesel air shaft ends far away from the diesel engine air intakes. The combustion air of the diesel is either normal aspirated or supercharged. When the engine is in normal aspirated air mode, air is drawn in via a rotary inletvalve into an airmanifold alongside the engine, from this manifold are separate ducts to the inletvalves on each cylinderhead. When the engines are running supercharged you clutch in the Roots blower, at the same time you rotates shut the aspirated air manifold inlet valves, as the roots blower discharge is directly connected to the aspirated air inlet manifold, the manifold is now becoming supercharged airmanifold. As all the air inlets are far away from the outlet of the dieselair shaft the drain of the shaft do not interfere.
Tore