I suspect that it was pre-IRS, since you mentioned the "roll over" option. I had two of those. The first one lived 2 months before my wife ran it off the road and hit a tree dead-on at 50mph. She was 6 months pregnant with my son. Pre- air bags. The passenger compartment was completely unharmed and both passengers were fine. The car performed beautifully, engine dropped, frame buckled like an accordion to absorb the energy. I had her in a new one in less than a week.
That being said I think the design of that vehicle had some flaws. The fact that the tires were to be inflated so low proves this in my mind. Although I never had any problem and drove through several Upstate NY winters. The vehicle was completely redesigned in 2002(?), with a wider chassis and IRS. It has an innovative frame feature at the rear wheels, where they eliminate the “hump”, cut a hole in the straight members and the half-shafts go through, instead of under. I originally went to the dealer to test drive an F150, but drove a 2002 2WD “Exploder” as well, and it was the best riding vehicle that I had ever been in.