You probably won't need to book ferry going over but coming back with a rig your size and especially if you need to get back by certain date, I would book the return. Marine atlantic told me they are fully booked in July/August.
Last time (we too are going this year shortly) we prebooked the going over, arrived a few days early and went the next day...return was via labrador.
This time we are winging it and will book once we have a better idea of when we will be returning. I like a more relaxed approach and seeing where life takes us.
We will mostly boondock while there but do get their park pass and stay at a few parks as they provide dumping, laundry/some and just some neat locations.
Sandbanks provincial park gets our vote and we will return there (check opening dates for your arrival)...check their amenities (no electric).
Don't drive in the dark...the darn moose dontcha know...too many, too dark.
