Are these screws that go into brass inserts in the back plastic piece? If so, I'd suggest drilling the head off - it's way too easy to crank them hard enough to break the plastic around the brass insert once you start forcing things. Once you've drilled the head off you've removed the clamping force so you can usually twist the remains out with your fingers, only occasionally do you need to grab it with pliers or vice grips...Kevin K said:I'm trying to get the plastic air filter boxes apart on my '01 748S. Most of the screws that hold the two pieces together won't budge. Before I stip one of them, can anyone recommend a way to get those screws out? Heat? I've tried WD-40 to no avail. I'd rather not have to use my extractor, but will if that's the only way.