how would you go about molding a nacelle?

[raser13]

hey guys, i've have a minimal knowledge of resin casting. i've used the two part putty style mold making material but i've just graduated to using the two part pourable style that they sell at hobby lobby with good results. the only thing is that the parts that i've molded in the past have all been flat on one side. think enterprise bridges,planetary sesors, impulse engine crystals. now what i need to cast is a little different. there really isn't a "bottom" side. or a "flat" side to a nacelle. here's what i need to copy.

http://s1015.beta.photobucket.com/user/ ... sort=3&o=3

http://s1015.beta.photobucket.com/user/ ... sort=3&o=2

http://s1015.beta.photobucket.com/user/ ... sort=3&o=0

so those of you that do alot of this type of thing, how would you go about molding this up??