Use threadlock not PTFE, thats for plumbers lads
the two I did were stuck but managed to get them loose, ptfe taped them, and got them back in, probably overtightly but they're in at least. It's the bottom, i.e. the most important outlet that is ruined
as far as im aware there was no thread difference on mine the red nipple i received was the extra nipple i bought, unless maybe i got it right out of luck.
haha, it's the black car...or the 666 in my username, I'm sure of it . For rethreading, I just get a standard tap & die?