I'm not an expert on this stuff, but...
Getting an overnight permit to dayhike because dayhiking permits aren't available is considered by most to be an abuse of the system, and the rangers may ask to see your bear canister.
I do not believe camping is permitted at LPL, so if you were saying you were going to sleep there Friday night, I don't think that plan is a good one.
If your intention is to backpack (overnight) the MMWT, I would suggest trying for an overnight walk-in permit, and then camping in an approved area.
Good luck and have fun.
J-G
