I know the K&P trail very well.Used it for years on the snowmobile and atv year round.I was up there this past weekend for a tour.
Your not gonna find many Backcountry Lakes off of it,you gotta go way further into the bush for those.For any Pristine Lakes with Trout your not going to be able to access them with your truck at all,there ATV access only for the most part unless you have a highly modified Rig.
I'm back in there all summer long,I know trails up around those parts that take you 3-4hrs to get 2km's on an ATV.
You also need to purchase a Trail Permit for trails up around those parts,most of them are on Crown Land.