Well, with a 98, he would have a TJ, which should have an even more stable suspension on the road.
That being said, while the Wrangler has the same "pulling" capacity as the Cherokee, the reason the Wrangler's listed "towing" capacity is so much lower than the Cherokee and other similarly built trucks, is that with its very short wheelbase, the vehicle can get pushed around by the trailer very easily. Brakes on the trailer will help with this to a degree.
Does your trailer have bias, or radial tires. Bias tires tend to follow better on a trailer. Getting the tongue weight right, and the trailer balanced correctly also very important, as is securing the load (something this large should probably be bolted down, welded down, or chained, but I'm not providing any rigging advice here).
The SA200 weighs in at around 1300lbs. Taking it slow may help, but maybe for the long trip, a bigger truck would do better. Its all up to your comfort level.