As far as the floor, you can make a LOT of room with an acetylene torch and an 8 lb hammer. I cleared about 2" at the bellhousing just by heating and stretching the metal.

Scott 1956 Dodge Custom Royal Lancer (408 Stroker, 4 Wheel Disc Brakes, Rack & Pinion, 6 speed) 2002 Dodge Ram 1500 Quad Cab 1976 Corvette