Anyone have any idea on what size cakes to make? I am thinking it will either serve a little less (a 10 inch and 6 inch square at 68 servings) or considerabley more. Any ideas on how to get it close to 75?

Thanks!

10" and 8" will serve 82 according to the Wilton chart. That's about as close as I see besides the 68 serving that you mentioned.