You are taking a bit longer ride, but there are some similar topics you want to look into:
Some infor you can find in this “Distance Training” thread: Distance Training
And more recent discussion in “Training for 100 mile ride”: Training for 100 mile ride
the “Who has completed a 100 mile ride?” is more like brag thread, but still you can get some contacts there… Who has completed a 100 mile ride?
And how’s your ride, would it be road ride? And will it be supported?