Ford calls their engine computer a Powertrain control module, a PCM
Some use engine control module, ECM, or engine control unit, ECU
But they all reference the same thing, the engine computer
1994 and earlier Rangers did have a separate Spark module, ICU(ignition control module), lol.
They were called ICM, TFI and EDIS, so 1994 and earlier had a PCM and a separate ICM
In 1995 Rangers got a new larger PCM, which is still in use in 2018, it is the EEC-V PCM
Spark control was now done by this PCM so no more ICMs
So if you have a 1995 or later model Ranger you just have the one PCM, but...........................
In 1995 Ford added a BCM(body control module), another "computer", it was called the GEM(generic electronic module), it controlled cab electrics, i.e. wipers, dome lights, power windows and door locks, 4x4 system
That lasted until 2001, when Ford switched the BCM to the SJB(smart junction box), but it didn't control 4x4 system, there was a separate 4x4 Module for that in 2001 and up Rangers
In 2004 and up Rangers Ford added another "computer", in the instrument cluster, all digital dash, still used analog "looking" gauges but they were all digital in the back
Ford called this the HEC(hybrid electronic cluster)
So no, not a dumb question