MCI 9 Side walls?

[chazwood]

those window look like after market (with a deeper profile than the om windows right? )

I was wondering about what to do with original
windows that are already flush on the inside.

[Tony LEE]

I took the chair rail off and removed the decorative panel and the dimple plate to leave a clean surface for fitting wall lining and furniture.

Still kept the original AC but just fitted a grill to blast the air into the interior. Depends on your passenger numbers and where they sit whether you need something more elaborate.

[NJT5047]

those window look like after market (with a deeper profile than the om windows right? )

I was wondering about what to do with original
windows that are already flush on the inside.

The windows pictured in the second pic are the OEM windows.  That's a 6 year old picture.   The pic with with wifey in it shows the Pen windows.  The Pen windows are a little deeper because they are screwed on top of the OEM window frame.  However, both use the OEM rubber moulding and frame.  The rubber window trim is over wall paper that Terri  cut out and glued to the OEM walls.  It's under the OEM rubber trim. I worked around the windows when furring out the bus walls.     The 1.5" oak trim covers the 3/4" furred out walls.   Other than that, the area around the window walls is OEM.  At the ends where there is a 3/4" ledge...I cut a piece of oak to fit into the end of the frame.  Tidied it right up.   
Pen windows fit (the ones that I used) into the OEM MCI window frames.  They'll still swing out.  The interior wall around the windows isn't modified.  The Pen windows could be removed and the OEMs put back in.   
The oak trim just catches the lower OEM rubber moulding.  It pulled up nice. 
There are other ways to address this area.   A popular method is to build window boxes that literally cover the area.  I didn't want the boxes encroaching on my interior, but they look good.   
You can also frame the window openings with cabinet grade 3/4" oak..or whatever matches your interior wood choice.   That's gonna cost a bundle, but it'll look great. 
I'm assuming that you've removed the aluminum handles and all of the interior wood grain paneling.
As Tony Lee decsribes, all my above the floor interior HVAC duct was removed.  I've go oak distribution boxes over them.  Home Depot...about $30 bucks each for the two big outlets...much less for the inlets.
If you want to use pleated RV style shades, a window box works best since it captures them.  If you plan on drapes, flat windows lend better for that.  Our heavy drapes are really useful in cold weather.  Makes a huge difference in heatability...and coolability.  Even with the dual pane windows. 
Yet another option is to skin over the side windows, furr out the whole interior, and cut in new custom made windows.  Then you can use RV style trim rings on the interior.   Be neat...and expensive.  7 RV windows would be in the $3K range.  That's what my Pen windows cost.  Still, you gain sliding dual pane tinted windows with screens. 
Hope I haven't confused you too much!  JR

[chazwood]

Huh?
















just kidding ....made perfect sense to me.