If y'all do visit the arboretum, may I also invite you to visit the Florida Southern College campus, just 20 miles west of there, in Lakeland. Until recently, we had the 3rd largest public collection of citrus (after Riverside and the Fla Arboretum). Recently, the college has removed 40-some trees, which really hurt the diversity of the collection, but we still have a good number of trees of some very interesting varieties. Let me know if you're coming, and I'll try to be available for the grand tour.
Malcolm