I am interested in this, as I also use FastComet shared hosting for my Ghost-O-Matic website.
Currently on that site I am running Ghost v4.4.0:
(Because of this recent issue I will do some testing before I update the Ghost version for that site.)
Here is my setup at FastComet . . .
For the Ghost-O-Matic site (which has been reliably up for 3 years now) I use FastComet’s Ghost Cloud Hosting:
I am on the Fast Cloud Extra Plan (so their highest shared hosting tier):
Within that hosting account I am using the Cpanel interface:
For creating (and stopping/restarting) the Ghost instance I am using their Ghost Publishing Platform interface:
I am using the File Manager in the Cpanel in my FastComet hosting account to directly edit my Ghost theme files: