Now I'm finally getting around to doing this, I noticed the 'main' rad cap (not the overflow) is a strange Motorcraft part without the conventional "ears" and has "DO NOT REMOVE" written (in four languages) on it. This may be a dumb question, but that warning is not to be taken literally, correct? (other than when the engine is hot of course!)
If it is, how would you ever refill the system ?? Clearly, with the overflow tank cap sitting lower than the main cap it would never fill that way other than by many repeated uses of the back 'hot syphon', and while jacking the car helps release air locks it's never going to be possible to fill other than via the top hose - surely not? - or the main cap