Any chance You have access to a lift? If you do you can lift the cab with the nose still on it. Just run some 2"x4"s under the rockers and lift them with the arms of the lift. Another thing that comes to mind is to drill some holes in the floor to gain access to the body mount bolts. Spray them down with penetrating oil and heat them with a torch if you have to, It's a pain if you break them off.