Hope this will help.
To begin DO NOT USE ETHER/STARTING FLUIDS, anyone telling you to do so needs to be ignored due to their ignorance, they are going to cost you more money, I've scrapped out sever trucks ruined with what I call "idiot spray".
The powerstroke 7.3 and T444E are mostly the same engine, this will also help with others as well but I thought since it's cold I'd throw these videos out there and hopefully it helps someone out.
https://youtu.be/igEKn2uJYCc
How to bypass the glow plug relay if it's bad.
https://youtu.be/Lz2KLpeIx4c