Thanks for all of the comments. With a 3.2, I don't think the weight of the steel vs fibreglass is a primary concern.
My concern with fibreglass echoes the ones posted above, primarily fitment, especially with the fenders. The discovery of the car pictured below, has me leaning in the steel direction again.
Car is from this for sale posting
http://forums.pelicanparts.com/porsche-cars-sale/731427-1971-911t-3-0-coupe.html
I guess I will have to see what steel parts I can find and at what cost. I know a new pair of fenders from Porsche is going to run ~$2500 and I would like to avoid that.
Todd