Yes... I have cut up fibreglass dinghies (14 ft ish) ,kerosene tanks, tractor rear tyres (not the bead), fibreglass lorry trailer roofs Fiberglass cuts no trouble(check for reinforcing) however I recommend you do everything you can to keep the fibres out of your lungs and eyes. It also itches like hell, so stop it getting down your shirt somehow, and reckon on a good long shower when you are done and before you cool down, Or you will regret it.
Strangest thing I ever cut up was a 5 gal drum solid full of lead which a builder gave me after they had it in their bonfire for a day....fed it with all the old lead pipe they could find....which I wanted for shotgun pellets, they said I could have it if I could get it out of their pickup alone. Well I couldn't, so lifted it out with a loader, it might have weighed 450 lbs ish.
Cut it into cookies once I got the tin off, then smaller with a sharp axe. still got a few bits of it after 35yrs. Made a lot of shot, and various projectiles. Would have made a good advert for Jonsereds !