Here's a good how to I found, on resin casting: http://www.starshipmodeler.com/basics/jc_molds.htm

Same basic principal. I would make the mold out of rubber too, so it would be easy to pull the hoods out, just need to liberally coat the inside with petroleum jelly or something, so they don't fuse together.

You know, I need to get back working on this project.