Is it just me or does sketchup really suck for this type of thing? Back when I was pursuing an engineering degree I had a chance to use EE and it kicked ass compared to sketchup for this easy task.
I didn't feel like re-installing my 3dsmax copy given how huge it is but I have a feeling even it would have been easier to use >_<
I guess if I felt like blowing $500 I could then import a dwg from illustrator into sketchup but it isn't worth it. I think when I go to print this project I am doing it through illustrator and scaling it as needed.
All that said the below has a 4 degree down angle from top and 8 degree from bottom. There are really two bulkheads here, the seat and the lower which will likely be intersected by the rear tire / swing-arm etc. No Kamm shown and I was thinking I might just Kamm the head rest enough to fit my license plate vertically near the rear.
Thoughts? Oh if you can't tell the top profile has the ideal shape. The ribs colored on right are accurate and properly scaled for the degrees indicated, the sketchup stuff is relatively close.
FirstTailMockup