I usually heat up the stubborn Loctite'd fasteners, works pretty good. Propane torch, heat gun, whatever's laying around. If there are parts nearby that may melt, then a soldering iron applied to the fastener works nicely. Gentle movement back and forth to free it up usually will get it moving.
I've also read that acetone will dissolve it, but haven't had much success with that method, plus it can damage finishes etc if it gets splashed around.
And brass inserts are easily deformed, so using vice grips, pliers, etc, can easily crush the brass insert onto the bolt threads. The tighter you make it, the more difficult it is to remove. Makes it difficult remove stubborn inserts, apply to much gripping force and it deforms and you're done.