1995 Ranger is Ford OBD2 but it did have some issues, 1996 was when it was universal OBD2 so just a heads up
Scan Gauge makes a display that can do MPG but you have to set it up for engine and vehicle and then "tell it" how much gasoline you put in each time you add fuel, it can access speedometer signal so can keep track of miles driven ASSUMING you have stock size tires so speed signal is acurrate.
It can do real time MPG estimate using engine size, throttle position, RPMs and air flow, basically shows you when you are getting best fuel economy while driving(like a vacuum gauge can), but..................
Its not capable of actual MPG because if engine was running rich or lean it wouldn't know that, it has no "fuel flow" data because the Ranger has no fuel flow sensor