I can't wait to hear about it. I was going to do one two days ago, but it was a 5 gal. recipe and I chickened out. So instead of that, I used 1 grapefruit, 2 lemons, and 2 oranges. I'll let you know how mine turned out as well!
Also, do you plan on using the entire grapefruit, or just the zest and fruit?