The ATC trailers that I have looked at are nice pieces. A friend has one of the upper end units and I would love to have it. You are doing the right thing keeping the weight down. I would also use a weight distribution hitch and dampener so you can control the wag. I pulled a 20' enclosed just a short time with my 1/2 ton Supercrew. Crossed a river bridge running 60 mph with 45 mph gusting cross wind. You should have seen that white knuckle ride. LOL Granted my Supercrew is more of a car with a bed than a real truck. Just be as safe as you can. I wouldn't want to see any racer have a wreck.
That same day the wind was so bad wasn't much fun at the track either. Didn't mean to sound like an ass in my earlier reply. Sometimes funny doesn't translate.
Curtis