Just bypass the heater control valve for now to rule that out and be careful how much coolant you put in as it's surprising how much is held in the engine you don't know about,I've had this happen loads of times.
Fords in general are pretty forgiving when it comes to bleeding etc,google e36 coolant issues to see a total nightmare of a car to bleed!!!
Sometimes it can help to put slightly less coolant in,run it up to temp,knock the engine off,remove the coolant cap when cold enough and leave it off overnight to let any bubbles escape.
Oh another one I've thought of on them is to take the small pipe that leads back to the expansion tank at the tank and bleed it that way.
Heater valves are hugely common failures on these,I've got one to do on the ka when I get back.