Just bought the '94-'04 FR500 Mustang steering wheel for my Explorer. I'm in the process of installing it now.
First of all, don't listen to Haynes. They say you need a steering wheel "bolt-type" puller. That won't work, you need a 2 jaw puller instead.
Second of all, I can tell you right now that the Mustang wheel is different than the Explorer. The Explorer plastic cruise control button housings will not bolt up to the Mustang wheel. The horn switches seem like they might bolt up, not exactly sure yet. The Mustang steering wheel metal frame certainly looks different than the Ex's, but I don't know if that will cause fitment problems.
I don't see any reason why the Ranger would be any different than the Explorer. But then again, I didn't see any reason why the Mustang would have been any different than the Explorer, but I was obviously wrong. You would think cars would be cheaper if manufacturers didn't unnecessarily make slight discrepancies in their parts for their different vehicles, but I guess that's just me.
Sorry I don't have any definite answers for you yet, but I need to get the gear puller to finish the job.