I think it may be too steep, yes. Did you by any chance see the "teardrop template" in my Kammback thread? It's a good starting place for figuring out the ideal shape/angle.
EDIT: here's the link to the post in question about the teardrop ...
http://ecomodder.com/forum/showthrea...html#post41136
I really like the material choice. If I could do mine in clear plastic, I probably would.