Brian, that is exactly what I did. I cut narrow pieces of plywood to the exact length for each set of cylinders to use. I had to open the Dormer and use a square to mark the roof panel. I approximated where the ball pivot would be, and drew parallel lines with the roof closed and latched. Across that line, I made marks at regular intervals, just the width of the square's ruler.Then I opened and use the stick to go from the first point to the body and Drew an arced line to the bottom parallel line.?
Eugene Breindel