If you want to change the player's faction back, you could simply change the faction number to the player's faction (player's faction number is : 13).
Or you could just delete the script you placed inside scripts.img and put a new one instead.
As for the text, its : TextPrintString("TEXT" 0,0)
The red zero is the number of seconds you want the text to last on the screen.
The Orange zero is the number of the text style, changing the number around, (like 1, 2 , 3 , 4 ect...) will change the text's style (by size, and I think by color aswell).