Some additional footage on changing a Ford Ranger Heater Core. I did not have to remove the blower motor and air conditioning unit to get to the nuts behind them. I was able to get to the bottom nuts (below the blower and ac) by removing the wheel well liner. As far as the Blower and A/C go, I did not want to discharge the system and I could not fold the hoses over because of clearance. I saw a video that talks about the nut behind the engine to remove the plenum from INSIDE the passenger compartment. There should have been a better way to do this...perhaps a stud that is inside the passenger compartment. The nut is right behind the engine and difficult to get at.
Ford, Ranger, Heater, Core, alebeau, 314