It almost looks impossible to remove the stock airbow from a 1st gen gixxer. The only way it seems to be possible is to first remove the engine. Not so!
I did it last night, after deciding to go with individual air filters. I wish I had of taken pics, but was too excited with my progress.
1. First, the carbs need to be removed, sucks, but you need to. Then remove the air filter from the box and unscrew the box screws and remove the top brackets.
2. Now twist the airbox counterclockwise, with some force, watching out for any interference with the alternator or anything, then tap the box for the final 1" movement with a rubber mallet. That should clear it from the frame and it will be free to move around sideways in the frame.
3. Now, push it in towards the carb area to get some rear clearance above the starter relay, and with a little move careful force, shove the carb tube part up and over the frame near the battery.
It will pop right out with no damage to anything.
My carbs were already out ( I couldn't get the carbs reinstalled with the box in place, part of my reason for going with individual filters.) and from that point, it took approx. 3 minutes to remove the airbox.
Reinstalling the box should be easy enough in the reverse order.
Hope this helps somebody out.