It really isn't that important.
Keep in mind:
~The kitchen shuts down during Wishes, and it takes about 25 minutes before they are completely up and running again, so give yourself time to order and get your food before the fireworks start.
~You are able to get up from your table to watch the fireworks (for most of the restaurant, the view is better if you go outside.)
~Anyone who visits CG primarily for the fireworks view is, imho, missing the point. The food and service are the main attractions, and the opportunity to view the fireworks from that great vantagepoint is simply a bonus.
~Make a seating that is at least 45 minutes prior to scheduled fireworks to ensure that you get your entrees in a timely manner, and have fun.