Window Spacing on South Park Passenger Cars

I've finally settled, after hours of studying photos, measuring photos, and performing calculations, on the window spacing which I'll be using.

Here are my rules:
#7&8 are identical
#6-8, #40-41, #45 have identical windows except for the number of panes of glass.
#6-8 have the same window spacing
#6 has little space between the last window and the corner molding
#6-8 have a space more than twice the width of the posts at each end

The equations are as follows:
for #6:
2e1+13w+12p=400
for #7-8:
2e2+15w+14p=476

There are a few additional equations based on the C&S folios, but the above are key.

e1 and e2 are the space at each end of the car, minus the corner molding
w is the window width
p is the post width
If e1=p=5", then w equals 25.38 and e2=12.5
Yep, I am an engineer...just not the fun kind which gets covered in soot.

That is confirmed by a drawing which was developed independently of me (thank you Dave).

Additionally, I've potentially developed my technique for simulating the tin metal roofs which were standard on 19th century narrow gauge (and SG) passenger cars. I'm looking forward to the OR&L cars reaching the market which will fund mold prep for the South Park cars. I think I'll do a few freight cars after I get these goodies on the market...freight cars don't require anywhere near the time and effort to prepare (although the unit cost isn't that much less).