Railrider 1 towers use the existing screw-plates on the 96-99 rack. You unscrew the 2 cross-bars and 2 flat bars and remove them. They come with 2 type of bolts, short ones (to use with the plates that come with the RailRider 1 for different trucks) and longer ones to use with the Pathfinder rack.
The installation is pretty simple and should take about 1hr or so depends on how good you are at measuring things.
I have this install on my '99 SE with the Yakima Load Warrior.
Here's a pic of the rack and the Warrior