Son was able to get us reservations for an overnight train from Paris to Florence last month (he booked at station in France). However, even though we have 1st class passes, we were only sleeping available were the 2nd class couchette for 6. There will be 4 of us traveling in our group. I assume they will probably assign 2 other people to our couchette. Anyone with experience with this-anything I should know it advance. I have tried to read as much as possible and have watched RS DVD's about train travel, but any last minute tips would be appreciated.
The only real advice I have is to lock the door from the inside when everyone is going to sleep. I traveled on a number of T6 couchettes and never had a problem other than the compartment being too warm.
All couchette compartments are the same size. The only difference is how many bunks are pulled down (4 or 6). If you pack light, not only will it be easier for you to haul your luggage on and off the train, you'll have more elbow room in your couchette.