Hello George.....
Here are a couple of pics of a nose cone plug I did last year. I use a ref. book purchased from Amazon, "Fiberglass & Other Composite Materials", and it provided most of the answers to my questions. I had absolutely no experience in fiberglass fabrication. Most importantly it covered the "do's & don'ts" when contructing a foam buck. What ever time you budget for the project multiply X 10.....btw I numbered all the pieces,then glued with liquid nail, filled seams with aerosol insulation foam. I used a carpenters keyhole saw and an air file with #36 grit paper to shape the plug, sealed with a latex exterior paint, then bondo and sanded to final finish, painted with laquer paint....making the mold off of the plug was another chapter....Good luck.