John, I don't know how I missed this, looks like you sent this several days ago - thank you so much!
Do you have any pics of everything you describe below? Especially the access panel, plenum, etc.?
And a specific question below.
My engine cover is 34.5" high from the floor (to allow the turbo to sit on top of the Roots blower) and extends forward 28.5" from the rear window to the top of the rear seat's angled backrest. The seat's base is 14" high at the front, sloping down to about 12" at the rear, and the vertical front of the seat is 47" forward of the rear window. There is a large access panel under the seat to allow easy access to the air compressor and hydraulic/PS pump on the rear of the engine. The engine's air intake plenum is on the passenger-side, and I'll be making a storage nook on the opposite side underneath the overhead cabinets for bedding etc.
Does the rear window mean the back wall of the bus or the last passenger window?