I would add one other thing. Get to know a stock eliminator owner who runs a stick car. Those guys have made improvements that I am not going to get into here. They are for the most part willing to let you look and ask questions regarding line-locks, 2-step module set ups and how they use them for launch control. I have just completed the same process and boy did I go to school! I had to travel 85 miles one way to take on such training but it is worth it. Good Luck...
He's running a stock 2014 auto. No real need for a 2-step or even a line-lock. It can be set up to launch from idle so the "launch rpm" is always the same.
'07 Mustang GT 4.6 Auto C&L cold air, 3.73 gears, Diablo tune, and MT drag radials.