I've done several trips incorporating both BWCA and Q permits.  I get a BWCA permit for the entire length of the trip and I reserve a Quetico permit for the first half (or whatever) of the trip.  You do need an RABC too and your passports so you can check back in at Ely on the way back.  Going in at PP you can do the Canada side of the lake first, check out the area on Canada side of Upper Basswood River Falls; then leave the Q and travel back along the US side.  Since I do not fish I cannot speak to fishing licenses.   :)