If the levelwind is stock, removing it will reduce the resistance of the spool a good bit. This can, depending on how far and hard you are throwing now, have a rather large impact on your distance. I can't give you an exact figure, but I'm sure someone will chime in with an estimate.
There are two ways to deal with the levelwind.
The first, which will add the most distance, is to remove the levelwind mechanism completely and either remove the transition gear from the left sideplate or replace the clicker cog with a speed bushing. I prefer CT reels for surf and pier fishing, so this is what I'd recommend. It will also reduce the likelihood of a shock knot getting caught in the levelwind eye and blowing up your reel.
The second option is to replace the levelwind with an engineered-for-distance levelwind. This will add in a ball bearing for the worm gear and several other additions that will make the levelwind run smoother, thereby reducing the braking effect on the spool.
Evan