Wiring isn't 100% universal in Rangers. There are at least 4 wiring harnesses (although for these purposes, we can throw out the EV Ranger). At least 2 of my '98s didn't have any of the wiring for fog lights. power windows, etc.
So, I had to grab all the wiring from under the hood (including the fuse block as my bare bones Ranger didn't have the busbar for the fog lights/power windows). Nor did it have any of the wiring from the firewall connector to lights.
Under the dash, you may need all the wiring from the firewall connector block to a. the relay block in dash; b. the GEM (GEM controls fog lights, so you can have fogs + low beams or high beams but not fogs and high beams). Note: There are 4 GEMs too, and you need a GEM which supports the fog lights.
Guys at JY left just charged me for 2 wiring harnesses and the GEM (I pulled the relay box apart and only took pieces which I needed).
On my 3rd Ranger (an XLT), the connectors for the lights were there, lower header panel, branching off from the lights circuit. (If you pull the lights from an existing Ranger, you will know where to look on yours).