I leave the line at 3k rpm.
In your case with your drag comp, I would suggest leaving around 3200-3300rpm or whatever you feel comfortable.
I only have only about 10 hooks, but also one win and a 2nd place.
Just take it up to the desired rpm, there is no "brake" pedal involved.
Slowly start letting the clutch pedal out then when you feel it start to grab keep letting it out and once you feel the tires start going go ahead and ease it out the rest of the way, then stab it to the floor!!
Make sure to adjust throttle to keep that launch engine speed up, so you dont die on the line.
Just try to do this without burning up your clutch (read too much slipping, too much boost etc. ).
You might try 4 Lo, 4th gear. Another choice could be 2nd Hi or 3rd Hi.
Its really not hard to do. But it does make you nervous!