Connor - you might try some Kroil penetrating oil
http://www.kanolabs.com/penLub.html#anchor173855. Better than PB blaster and best stuff I've ever used on seized fasteners. Give it a day or so to soak in after applying. A test engineer friend of mine who had a side business overhauling turbochargers discovered it and got Pratt & Whitney to start using it where seizing/oxidation of fasteners exposed to temperatures of 1200-1400F was a big problem! GFS used it to get his OB trim & tilt assembly apart when nothing else worked. A top notch hardware store may carry it, or you can order it direct or from Eastwood. Denny