Spec sheet from the 1973 brochure:
Spec sheet from the 1974 brochure:
Here is some information gather from the around the web (shout-out to participants over at www.fiberglassics.com). 
Spec sheet from the 1973 brochure:
Spec sheet from the 1974 brochure:
Here is some information gather from the around the web (shout-out to participants over at www.fiberglassics.com).