best way to remake a car part?

[eg6part]

For my car, a 95 civic, I wanted a bumper air duct to suck in cold air to a ram air intake. The only one I could find was 170 for CF and 140 for fiberglass. There wasn’t any way I was going to pay that much. So I took a fog light frame and made mold with a sock stretched over and applied fiberglass resin. I know its ghetto but that’s what I had to work with. Then I added fiberglass matting and sanded down to a shape that would fit and I liked. I put some body filler, sanded, primed, and painted it. I want to redo it right and try to put CF on the out side part that you see. I have had people in the area ask if I would make one for their car too.
So the hole thing is leading up to what is the best way to make a mold for it so I can make a new one fast and efficiently, with out putting in hours into making new ones one by one and having to constantly test fit. Here is a pic of what it is based off.

http://www.aj-racing.com/catalog/product.php?productid=588&cat=109&page=1

here is a link for how it all works

http://www.honda-tech.com/zerothread?id=1477899

Thanks for all the help in advance.

 

[patprimmer]

Use the existing part to make a number of moulds, then make batches.

Buy a book from the FRP raw materials suppliers with mould making and fabrication methods.

Regards

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