@Nitro: I had the same issue when building my friend's SG, we forgot the ground wire and I had to pull out the bushing.
I tried to put a screw down the bottom but that basswood was soft and I was scared the small screw was being pushed through the wood as the bushing was quite tight.

I ended up making a quick contraption with a bolt and a large washer to pull it out, check link below:
http://www.buildyourownguitar.com.au...l=1#post102014

Was pretty easy once I found the right parts.