Best way to cut/trim fiberglass fairings?

[sibriggs]

I like the control I get with a hacksaw blade held in gloved hands. Not a lot of dust as with a Dremel or other power tools and excellent control, so no mistakes. You can cut a couple of layers of glass with ease and follow the cut line, go at a cut speed that provides the least risk of cutting an area you didn't want cut. Use some coarse sand paper to finish off the edge.

[rocketman1988]

Permagrit tools cut fiberglass like butter

[Larry DeCamp]

The little diamond blade cuts like a scalpel, narrow kerf and small diameter allows relatively small radius cuts. Just FYI, all the Orthopedic fiberglass casts removed everyday are cut off with the oscillating blade to avoid cutting the patient, yet they devour fiberglass and resin like butter.