You DO need a class III hitch minimum for that sized boat and a class IV for peace of mind. I've been towing a long time and for those who asked, YES I did literally rip the ball right out of the bumper of Dakota some years back. And that was with only my tin Super-Guide. Some yahoo yanked out in front of me and I jammed on the breaks. When everything was done I had heard a real "whack" in the rear and the towing was really goofy, being only held on by the safety chains. I had ripped the ball completely loose, still in the tongue of the trailer which flew into my tailgate. I had to leave at a friends down the road until I got my hitch on. For what it's worth, look at the pros for these kinds of things. The people that depend on this equipment for their livelyhood don't bumper trailer, why should you with a $30k boat? For the extra $250, you will have what Tracker, your vehicle mfr, and the rest of the civilized world recommend for towing. Good luck.