you got some room but u got too cut out around the out side of the frame rails to give about and inch for the new frame to come up through. i was able to cut the floor and reweld it together after bending the floor to meat. i got some pics but i gota load em first and there on another computer i think.
you will have to raise it regardless. you wont have to go the full amount of your bodydrop, a good estimate is atleast half the amount of your bodydrop.
i would just raise it 2" and keep some space under thare.