Some pix of the cab's interior - unfortunately I found only two prototype shots which show only a few parts of the interior. Even whether there were two or three seats cannot be identified. My Overland model shows wrong rear doors (one on each side, whereas the prototype diagrams has a center door only) as well as the prototype shots show seats with folding back without armrests whereas the Overland has non-folding-seats with armrests, no brake stand, no air-shutter control and so on...
So here's my replication with a lot of 'modeler's license':
On the fireman's side there's some air-brake equipment with a releasing handle.
In the center one finds the throttle stand (according to the prototype photos the throttle looked similar to those found in a streetcar). Additionally (partially hidden by the engineer's seat) there's the control for the front shutters behind the front grill (it cannot deny its descent from a steam-engine's throttle). The independent air-brake controllers are located on the engineer's right.
All parts are fixed to the cab's main floor. The front of the cab's floor is slightly raised, with screens on the step covering the cab-heater.
And with engineer & fireman in place
Further parts are mounted in the shell - the cab-signal box in the center and some gauges on the engineer's side.
Fixed to the center pillar are two prominent fans for defrosting/defogging the front windows.