Welcome MichUTurn, and congratulations on your new 5th wheel.
Is your 266RL a Laredo?? If so, we have the 265RL (no bedroom slide) model... and there's a few other Laredo owners here too.
'Backing' and 'turning' a 5th wheel is a bit different than a travel trailer. Your pivot point (obviously) & tracking will change, so give yourself plenty of room for wider turns. And, always be aware of your 12ft+ height... *looking up* for low limbs, over-hangs, bridge heights, etc. will soon become 2nd nature.
Just a few things to keep in mind... and I think you're going to be very pleased with the towing 'difference'.
Enjoy your new 5th wheel, and enjoy the journey!!
Terri [& DH Kevin]