Just so you know, we don't know the file format for every file. If it's just a bunch of random characters, it's probably a .zip or .jar.
command /setline <number> <text>:
aliases: /sl
permission: admin.setline
trigger:
if targeted block is not a sign:
send "&7[&eSetLine&7] &cTarget block is not a sign!"
stop
set {_line} to arg-1
set {_newtext} to colored arg-2
if arg-2 is "clear":
set {_newtext} to ""
set line {_line} of targeted block to {_newtext}
send "&7[&eSetLine&7] Line &f%{_line}% &7changed to &f'%colored arg-2%&r&f'&7."