I don't know that you need a guided tour. You don't drink all that much bourbon at the tastings themselves and if you do tours of the facilities, then there will be gaps between tastings that should help avoid getting too much to drink. However, if you have drinks after the tastings, that may change things.
Note that some tours require reservations, such as with Rabbit Hole and I think Buffalo Trace.
Buffalo trace you just show up, but you may have to wait. Worth it though. The property is incredible.
Just opened my Michter’s 10 year single barrel. Pretty outstanding.