From what i've heard about the ranger beds are that the 93+ years are actually a tapered beds where as its wider in the front then at the rear & the 92 & older are straight from front to back.
I just ran out to measure my 2003 bed thats on my 94 ranger & the tapered measurements are the outside of the bed ,but the inside rails are straight from front to back & measure 54.250, so if your inside rails are approximately the same then it should work ,but the front may be wider on the topper especially if its a fiberglass. If its an aluminum topper then it will probably be straight front to back.