I may not be the best person to answer, but I'll try, since no one else has. I think you need at least a 10% margin over GVWR, and you have that. If you will be towing in the mountainous West, you need at least another 10%, and 20% would be better. I would say that puts you just at your tow capacity, so it is doable. That said, we just got back from towing a trailer of that weight over steep, twisty roads between the CA Mendocino coast and the Central Valley with a V8 4Runner, 7000# capacity, and we were in 3rd quite a bit, 2nd once. That was at reasonably low altitudes. It may depend on how often you plan to go and where (and how patient you are).
One other suggestion is to repost your question with a title that indicates what your question is. You might get some better answers, especially from someone who has towed with a similar vehicle.