You''re a real funny guy.
I think he meant to be, but for what you are asking, he has a point... You may have the wrong trailer.
I've pulled mine with my 4.0L Wrangler, and they're just too dang big! (Too wide at least!) Really this trailer is even wider than my full size truck, so it's just too much for my Jeep to pull down the road. (Wind drag is HORRIBLE behind the Jeep!) While it would be cool to narrow it by about 2', that would be a LOT of work, and the trailers aren't assembled in a way that makes them easy to disassemble.
The box is pretty much part of the frame, and the frame is pretty much part of the box, and the entire thing is rivited/huck bolted aluminum, except for the straight part of the tongue that extends under the trailer, the coupler, and the axle.
You've done the easiest part: each of the 37" runflats weighs 160lbs!! The 285's on aluminum wheels that I mounted weighed 75lbs each, so I dropped 170lbs there. Sounds like you dropped a little more with the 6-lug hubs, and likely lighter tires.
If you don't mind having a trailer w/o brakes, or don't mind converting to electric, getting the hydraulic surge assembly off the tongue and putting a light weight ball coupler on it would probably knock off another 75lbs or so. That would get you down to 1075lbs. If you put a lighter axle under it, and knocked off another 100lbs, you're down to 975lbs. With the way the trailer is built, mounting a leaf spring axle wouldn't be too simple though, and the trailer is still dang wide for a Jeep...
It's built heavy for a reason, and making it significantly lighter just isn't very easy.
The box also has the axle too far back to look good as a pickup bed, and probably too far back for proper tongue weight on a Jeep too... They're pretty tongue heavy when loaded, which my Jeep doesn't appreciate.
But have fun making it yours! For the money they are a great deal even if they're not ideal.