Man, I don't know if I would butcher the car down to nothing. You should easily be able to get the A-body down to about 3000 lbs by making sure there are zero options (manual steering, manual breaks), IF your car is a '74 or newer, it has reinforcements behind both bumpers that can be cut out. You can easily have a nice street car that weighs 3000-3100 pounds without butchering doors, glass, etc. If you can't get into the 11's with a 3100 lb car, then you need more motor. Focus on dialing in your 318 to perform. At 14.20's, you are nowhere near reaching the motors capability. I know a guy that got a 4100 lb truck into the mid 13's with a 318. Yes, a full size, long bed, 4100 lbs of steel, pickup cutt'n all the wind plus weight. But, your project, do as you please. I would just keep it street friendly.