The trailer weight ratings are very conservative and I wouldn't worry about the towing, personally. I have 7 trailers and all of them have been loaded WAY over their gvwr at some point or another and never an issue.
I say pull it and see how it feels. I think a lot of people are pulling over their truck/vehicle capacity more than they are stressing the trailer.

I pulled my tige with my wife's grand cherokee and it did fine. ~4500 lbs or so.
Technically it has the rating to pull the SA but there's no way in hell id do it and I think it's absurd that it's even legal.
I see people pulling these new heavy boats with things that have no business pulling them all the time.