Welcome to Healing Well! Glad you've joined us. You've definitely come to the right place. This forum helped me tremendously when I had my Nissen three years ago.
Here's a link to my recovery journal. It chronicles my first 19 days and offers some information that will be useful as you move toward your surgery.
Here's a link to some post-Nissen eating information:
This link will provide some good information as well:
Be sure to stick around and ask any questions you may have both before and after your surgery.
There are many here who have been through the surgery, so they will understand what you're going through.
It sounds like you've made an excellent decision.