Little Help Please

Got an 8.15 out of it with the new carb. 60' was 1.810. Ran better didn't run out of gas. Still didn't need 3rd gear. Shifted at 6000 and was running about that at the end. My shift light would just come on. I tried short shifting it at 5800 and it slowed down. Tried shifting at 6200 and it slowed down so 6000 is its sweet spot. Really need a 7.80 out of it. I don't want to take away any drivability. I have always hated nitrous, but have read alot on it in the last week and am thinking about a 125 shot. They claim a fairly stock motor with cast pistons will last if tuned right at a 125 shot. I have the MSD ignition that will retard the timing as soon as I turn the nitrous on. So that is nice. Just wondering if a 125 shot will get me down to a 7.80 I really don't want much faster, Our track requires a cage at 7.50. And I want to leave the car stock looking. Some opinions on the nitrous please. My good friend has a 62 nova that is pretty much just a drag car. 355 tunnelran 2 4's. 4000 stall, 456 gear. He is running high 7.70 low 7.80's. I want to run with him through my exhaust and on radials, and full interior. He predicted my car wouldn't break an 8.80 first time out and it ran a 8.23. So I would like to see the look when I run a 7.80. Help me out.