I did this to my sedan and the same thing happened, but not even close to as bad...I ended up leaving some letters and going to a body shop and they finished and buffed my entire trunk for $20...I still need a repaint because of the cloth I used caused some pretty deep scratches...they used floss to take the letters off and then had a special rubberized polish wheel to take the adhesive off...way worth the money in the long run

 

Wow that's rough. Glad everything worked out though. I was going to debadge my G as well, but now I won't do it. Not worth the risk. By the way, it looks really clean debadged.