Here is what I have. I used a flexible scale and measured along the face of the channel. (The face that steps down from the roof)
From the Center line to D1 = 1 1/2"
From D1 to D2 = 8 3/4"
From D2 to D3 = 8 3/8"
From D3 to D4 = 7"
from D4 to D5 = 8"
From the Center line to P1 = 4 3/4"
From P1 to P2 = 8 3/4"
From P2 to P3 = 8 1/2"
From P3 to P4 = 7"
From P4 to P5 = 7 1/2"
From P5 to P6 = 7 1/4"
Hope it makes sense, if you have any questions, please ask.