Yup, it will definitely fit for I have the same size I bought from a guy off Craig's List. You will need the Surco J100 adapters for a 1998 5.2 or 4.0. These brackets will not fit
a 1998 5.9 for the rails are different for this model/year and are lower profile. The good thing is if you plan on using your factory crossbars to mount lights, it will be the correct spacing to still fit the front and rear crossbars and the Surco rack. The only thing I do not like about Surco is they a very proud of their adapters, hence why I mounted my lights on my crossbar versus using their adapters. I spent $85 for part #1108 (Hi-Lift Carrier) and $85 for the J100 adapters. And will need to spend another $85 for the shovel and axe carrier... you see where this is going.
I see Amazon has them for about $20 cheaper...