Here's the link:
http://graviteam.com/forum/index.php?topic=529.0
Not to over-simplify matters, there's a right and not-so-right way to do things like using the tank's gun, but my method is to eyeball it!
Raise the gun higher for longer-distance targets; give some lead for moving targets. See where the shell lands and adjust accordingly. And that's my quick and dirty way to do it
